Previous Year Paper

UPPSC AE Civil 13 Dec 2020 Official Paper - II (Previous Year Paper)

Held in 2020

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General Studies (25 questions)

Question 1

Match List-I with List-II and select the correct answer using the codes given below the lists:

List – I (Tribes)List – II (States)
(A) Tharus1. Madhya Pradesh
(B) Todas2. Jharkhand
(C) Santhal3. Uttarakhand
(D) Gond4. Tamil Nadu

 

Choose the correct option from those given below:

  1. AOption (a)

    (A) - (1), (B) - (3), (C) - (4), (D) - (2)

  2. BOption (b)

    (A) - (4), (B) - (2), (C) - (1), (D) - (3)

  3. COption (c)

    (A) - (2), (B) - (1), (C) - (3), (D) - (4)

  4. DOption (d)

    (A) - (3), (B) - (4), (C) - (2), (D) - (1)

View answer & explanation

Correct answer

Answer: (d)D.

(A) - (3), (B) - (4), (C) - (2), (D) - (1)

Why this answer is correct

The correct answer is option 4.

Key Points

  • Gond is a tribe of Madhya Pradesh.
  • Gond tribe is one of the largest Adivasi communities.
  • The Gond called themselves Koi or Koiture.
  • They inhabited the dense forests of the Vindhyas, Satpura and Mandla in the Narmada region of the Amarkantak range for centuries.
  • Tharus is a tribe of Uttarakhand.
  • They are live in Khatima and Sitarganj tehsil of UdhamSingh Nagar district (Uttarakhand).
  • Todas is a tribe of Tamil Nadu.
  • Todas is a tribal group in the higher altitudes of the Nilgiris.
  • Santhal is a tribe of Jharkhand.
  • They are also called Manjhi.
  • The third-largest tribes of India are the Santhal Tribe.
  • This tribe habitation is mainly in the states of West Bengal, Bihar, Odisha, Jharkhand and Assam.

Additional Information

Important tribes of :

StateTribes
Madhya PradeshKharia, Bhils, Murias, Birhors, Bharia, Khond, Gonds
UttarakhandBhotia, Buksa, Jaunsari, Kol, Raji,  Khas, Raji, Tharu
Tamil Nadu.Kadar, Kanikar, Kotas, Todas
JharkhandSavar, Mundas, Santhals, Khaira

Question 2

‘Poshan Maah’ was celebrated by Government of India in the year 2020, in which of the following months?

  1. AOption (a)

    September

  2. BOption (b)

    August

  3. COption (c)

    July

  4. DOption (d)

    June

View answer & explanation

Correct answer

Answer: (a)A.

September

Why this answer is correct

The correct answer is September.

Key Points

  • Rashtriya Poshan Maah was celebrated in September 2020.
  • It was celebrated to promote nutrition among Women and Children.
  • Poshan Maah is celebrated every year to encourage Jan Bhagidaari in order to ensure health and nutrition for everyone.
  • Every year Poshan Maah is celebrated all over the country under POSHAN Abhiyaan, launched in 2018.
  • The importance of Nutrition in our lives was emphasized by Prime Minister Shri Narendra Modi in his popular programme “Mann ki Baat” on 30th August 2020.

Question 3

Match List-I with List-II and select the correct answer using the codes given below the lists:

List – I (States)List – II (Highest Peaks)
(A) Tamil Nadu1. Dhoopgarh
(B) Rajasthan2. Saramati
(C) Nagaland3. Guru Shikhar
(D) Madhya Pradesh4. Doda Betta

Choose the correct option from those given below:

  1. AOption (a)

    (A) - (3), (B) - (4), (C) - (1), (D) - (2)

  2. BOption (b)

    (A) - (1), (B) - (2), (C) - (4), (D) - (3)

  3. COption (c)

    (A) - (4), (B) - (3), (C) - (2), (D) - (1)

  4. DOption (d)

    (A) - (2), (B) - (1), (C) - (3), (D) - (4)

View answer & explanation

Correct answer

Answer: (c)C.

(A) - (4), (B) - (3), (C) - (2), (D) - (1)

Why this answer is correct

The correct answer is (A) - (4), (B) - (3), (C) - (2), (D) - (1).

  • The highest Peak of Tamil Nadu is Doda Betta.
  • The highest peak of Tamil Nadu is Doddabetta and is a part of the Nilgiri Hills at the junction of the Western Ghats as well as the Eastern Ghats.
  • ​The highest peak of Rajasthan is Guru Shikhar.
  • ​Guru Shikhar, a peak in the Arbuda Mountains of Rajasthan, is the highest point of the Aravalli Range. The peak is named Guru Shikhar or “peak of the guru” after Dattatreya, an incarnation of Vishnu.
  • ​The highest Peak of Nagaland is Saramati.
  • ​Standing at an altitude of 3841 m, Saramati is the highest peak in the state of Nagaland and occupies a place of pride in the heart of its residents.
  • ​The highest peak of Madhya Pradesh is Dhoopgarh.
  • The Dhupgarh Peak (1,350 metres), near Pachmarhi in south-central Madhya Pradesh, is the state's highest point.

Question 4

‘Five Star Village Scheme’ started by Government of India in September 2020 relates to which one of the following?

  1. AOption (a)

    Electricity Supply

  2. BOption (b)

    Postal Service Schemes

  3. COption (c)

    Health Services

  4. DOption (d)

    Primary Education

View answer & explanation

Correct answer

Answer: (b)B.

Postal Service Schemes

Why this answer is correct

The correct answer is Postal Service Schemes.

  • The Department of Posts launched a scheme called Five Star Villages.
  • It is to ensure universal coverage of flagship postal schemes in rural areas of the country.
  • The scheme is being launched on a pilot basis in Maharashtra.
  • It bridges the gaps for generating public awareness and reach of postal products and services, mainly in interior villages.
  • Under the Five Star Village scheme, all postal products and services are going to be made available and marketed, and publicized at the village level.
  • The schemes covered under the Five Star scheme include:
  • ​Savings Bank accounts, Recurrent Deposit Accounts, NSC / KVP certificates.
  • Sukanya Samridhi Accounts/ PPF Accounts.
  • Funded Post Office Savings Account linked India Post Payments Bank Accounts.
  • Postal Life Insurance Policy/Rural Postal Life Insurance Policy.
  • Pradhan Mantri Suraksha Bima Yojana Account / Pradhan Mantri Jeevan Jyoti Bima Yojana Account.

Question 5

Match List-I with List-II and select the correct answer using the codes given below the lists:

List – IList – II
(A) Nokrek1. Uttarakhand
(B) Agasthyamalai2. Arunachal Pradesh
(C) Nandadevi3. Kerala
(D) Dehang Debang4. Meghalaya

 

Choose the correct option from those given below:

  1. AOption (a)

    (A) - (4), (B) - (3), (C) - (1), (D) - (2)

  2. BOption (b)

    (A) - (4), (B) - (3), (C) - (2), (D) - (1)

  3. COption (c)

    (A) - (3), (B) - (4), (C) - (1), (D) - (2)

  4. DOption (d)

    (A) - (2), (B) - (3), (C) - (4), (D) - (1)

View answer & explanation

Correct answer

Answer: (a)A.

(A) - (4), (B) - (3), (C) - (1), (D) - (2)

Why this answer is correct

The correct answer is (A) - (4), (B) - (3), (C) - (1), (D) - (2).

Key Points

 In the given table, Biosphere reserves are given.  These are biosphere reserve of states:

  • Nokrek is a biosphere reserve in Meghalaya.

  • The Nokrek Biosphere Reserve is located in the northeast of India on the Tura Range, which forms part of the Meghalaya Plateau.

  • ​Agasthyamalai is a biosphere reserve in Kerala.

  • ​The Agasthyamala Biosphere Reserve (ABR) has got its name into UNESCO’s World Network of Biosphere Reserves (BR).

  • It was established in 2001 and straddles the border of Kollam and Thiruvananthapuram Districts in Kerala and Tirunelveli and Kanyakumari Districts in Tamil Nadu, South India at the southern end of the Western Ghats.

  • Nandadevi is a biosphere reserve in Uttarakhand.

  • Nanda Devi Biosphere Reserve, located in the Himalayan Mountains in the northern part of the country.

  • It includes core areas of the Nanda Devi and Valley of Flowers National Parks, which are one World Heritage site.

  • ​​​Dehang Debang is a biosphere reserve in Arunachal Pradesh.

  • Dihang-Dibang or Dehang-Debang is a biosphere reserve constituted in 1998.

  • It is in the Indian state of Arunachal Pradesh.

  • Biosphere reserves are areas of terrestrial and coastal ecosystems promoting solutions to reconcile the conservation of biodiversity with its sustainable use.

  • They are internationally recognized, nominated by national governments, and remain under the sovereign jurisdiction of the states where they are located.

  • They often include one or more National Parks and/or preserves, along with buffer zones that are open to some economic uses. Protection is granted not only to the flora and fauna of the protected region, but also to the human communities who inhabit these regions, and their ways of life.

Question 6

How many teachers from Uttar Pradesh were selected for ‘National Award’ on Teachers day 5th Sept. 2020?

  1. AOption (a)

    Six

  2. BOption (b)

    Five

  3. COption (c)

    Four

  4. DOption (d)

    Three

View answer & explanation

Correct answer

Answer: (d)D.

Three

Why this answer is correct

The correct answer is Three.

Key Points

  • Three teachers from Uttar Pradesh were selected for the 'National Award' on teacher day.
  • The three from UP are — Mohammed Ishrat Ali, head teacher in a primary school, Rajwana in Mainpuri; Snehil Pandey, head teacher in a primary school Soharamau, Nawabganj in Unnao; and Vikas Kumar, principal, SD Inter College Meerapur, in Muzaffarnagar
  • Union Education Ministry inferred the National Award to Teachers as a way of recognizing their achievements in the field of education.
  • The awards were conferred by President Ram Nath Kovind on the occasion of Teacher's Day on September 5, 2020.
  • 47 teachers have been selected by the government for 'National Awards to Teachers 2020.

 

Additional Information

  • Teacher’s Day is celebrated across India today to honour Dr. Sarvepalli Radhakrishnan.
  • It is observed annually on September 5, as Dr. Radhakrishnan was born on September 5, 1888.
  • Dr. Sarvepalli Radhakrishnan was India's first Vice President and second President.
  • Teachers' Day was first celebrated in 1962, the year he became the second President of India.
  • Since then, the day has been celebrated every year. Dr. Radhakrishnan highly believed that teachers should be the best minds in the country.

Question 7

‘Leopold Matrix’ is associated with

  1. AOption (a)

    Weather Forecasting

  2. BOption (b)

    Disaster Management

  3. COption (c)

    Environmental Impact Assessment Method

  4. DOption (d)

    Environmental Law

View answer & explanation

Correct answer

Answer: (c)C.

Environmental Impact Assessment Method

Why this answer is correct

The correct answer is Environmental Impact Assessment Method.

  • 'Leopold Matrix’ is associated with Environmental Impact Assessment Method.
  • It is a procedure for the evaluation of the effect or impact of a proposed development on the environment.​

 

Important Points

  • Environmental Impact Assessment (EIA) is a process of evaluating the likely environmental impacts of a proposed project or development, taking into account inter-related socio-economic, cultural and human-health impacts, both beneficial and adverse.
  • It is statutorily backed by the Environment Protection Act, 1986 which contains various provisions on EIA methodology and process.
  • UNEP defines Environmental Impact Assessment (EIA) as a tool used to identify the environmental, social and economic impacts of a project prior to decision-making.
  • It aims to predict environmental impacts at an early stage in project planning and design, find ways and means to reduce adverse impacts, shape projects to suit the local environment and present the predictions and options to decision-makers.

Question 8

As per the results of ‘Swachh Sarvekshan 2020’, announced by Ministry of Housing and Urban Affairs on 20th August 2020, which is the cleanest City in Uttar Pradesh?

  1. AOption (a)

    Agra

  2. BOption (b)

    Ghaziabad

  3. COption (c)

    Lucknow

  4. DOption (d)

    Prayagraj

View answer & explanation

Correct answer

Answer: (c)C.

Lucknow

Why this answer is correct

The correct answer is Lucknow​.

Key Points

  • As announced by the Ministry of Housing and Urban Affairs, Lucknow is the cleanest city in Uttar Pradesh.
  • Swachh Survekshan 2020 report was released by the Union Housing and Urban Affairs Ministry.
  • Swachh Survekshan 2020 covered 4,242 cities, 62 cantonment boards and 92 Ganga towns.
  • This survey was carried out in 28 days.

 

Additional Information

Swachh Survekshan 2020

  • Indore was ranked the cleanest city in the overall category this year followed by Surat and Navi Mumbai.
  • Chhattisgarh is the cleanest state in the category of states with more than 100 urban local bodies.
  • Ahmedabad is India’s cleanest Megacity.
  • New Delhi is the cleanest capital city.
  • Chhattisgarh’s Ambikapur is the cleanest smallest city.
  • Cleanest Cantonment: Jalandhar Cantt, Punjab.

Question 9

States get share of the revenue from

  1. AOption (a)

    Income Tax

  2. BOption (b)

    Customs Revenue

  3. COption (c)

    Excise Tax

  4. DOption (d)

    Surcharge on Income Tax

View answer & explanation

Correct answer

Answer: (c)C.

Excise Tax

Why this answer is correct

The correct answer is Excise tax.

Key Points

  • The state gets a share of the revenue from the Excise tax.
  • Excise tax is a form of indirect tax that is levied by the Central Government of India for the production, sale, or license of certain goods.
  • It is also collected by state governments for alcohol and narcotics.
  • GST has now subsumed a number of indirect taxes including excise tax.
  • This means excise tax, does not exist in India except on a few items such as **liquor and petroleum. **​

Additional Information

Income taxIncome tax is a type of tax that governments impose on income generated by businesses and individuals within their jurisdiction. Income taxes are a source of revenue for governments.
Custom revenueCustoms revenue is a tax imposed on imports and exports of goods
Surcharge on Income TaxSurcharge on income tax is levied on the tax payable, and not on the income generated.

Question 10

Who won the US Open Mens Tennis Singles Title on 14 th September, 2020?

  1. AOption (a)

    Alex Zverev

  2. BOption (b)

    Dominic Thiem

  3. COption (c)

    D. Medvedev

  4. DOption (d)

    P.C. Busta

View answer & explanation

Correct answer

Answer: (b)B.

Dominic Thiem

Why this answer is correct

The correct answer is Dominic Thiem.

Key Points

  • US Open Men's single title- Dominic Thiem (from Austria).
  • US Open Women's single- Naomi Osaka (from Japan).
  • The 2020 US Open was the 140th edition of tennis US open and the second Grand Slam event of the year.
  • It was held on outdoor hard courts at the USTA Billie Jean King National Tennis Center in Queens, New York.
  • It was held without spectators due to the COVID 19 pandemic.

Question 11

The Joint Sitting of the Indian Parliament for transacting a legislative business is presided over by

  1. AOption (a)

    The President of India

  2. BOption (b)

    The senior most Member of Parliament

  3. COption (c)

    The Chairman of the Rajya Sabha

  4. DOption (d)

    The Speaker of the Lok Sabha

View answer & explanation

Correct answer

Answer: (d)D.

The Speaker of the Lok Sabha

Why this answer is correct

The correct answer is The speaker of the Lok Sabha.

Key Points

  • The joint sitting of the Indian Parliament for transacting a legislative business is presided over by The speaker of the Lok sabha.
  • The joint sitting is called by the President.
  • In his absence of the speaker of the Lok sabha, the sitting is presided over by the Deputy Chairman of the Rajya Sabha.
  • The quorum to constitute a joint sitting: 1/10th of the total number of members of the House.
  • A joint sitting of both Houses of Parliament of the Indian Constitution given in Article 108.

 

 

Additional Information

Speaker of Lok Sabha

  • The speaker of Lok Sabha is a member who elected from amongst the members of the house. He chairs the house and no proceedings in the house take place in his absence.
  • 1st Lok Sabha Speaker – Ganesh Vasudev Mavalankar
  • 17th Lok Sabha elections (2019 General Elections), Om Birla is the speaker of Lok Sabha.

Question 12

Which of the following pairs is NOT correctly matched? Ancient name of the cities Modern name of the Cities?

  1. AOption (a)

    Esipattan-Saranath

  2. BOption (b)

    Dashapur-Mandsaur

  3. COption (c)

    Banvasi-Talkad

  4. DOption (d)

    Mahoday-Kannauj

View answer & explanation

Correct answer

Answer: (a)A.

Esipattan-Saranath

Why this answer is correct

The correct answer is Esipattan-Saranath.

Key Points

  • The anicient name of Kannauj is Mahoday.
  • Kannauj is one of the most ancient place in India having a rich archeological and cultural heritage.
  • The ancient name of this place is Kanyakubja or Mahodya (as per Balmiki Ramayana, Mahabharat and Puran) later name kanyakubja was changed as Kannauj the present name of the District.
  • ​The ancient name of Mandsaur is Dashpur.
  • ​Mandsaur was known as Dashpur in ancient times.
  • It is also said that the name originated from Mandodri, wife of Ravana. And the ancient name Dashpur was named after her husband Dashanand, the other name of Ravana.
  • The ancient name of Sarnath is Isipatana.
  • ​Sarnath has been variously known as Mrigadava.
  • Just 10 km north-east of Varanasi, near the confluence of the Ganga and Varuna Rivers in Uttar Pradesh, was Initially known as Isipatana.
  • The ancient name of Talkad is Banvasi.
  • Banavasi is an ancient town in Uttara Kannada in the state of Karnataka.

Question 13

Which Article of the Indian Constitution empowers Parliament to make law for implementing international agreements?

  1. AOption (a)

    Article 249

  2. BOption (b)

    Article 250

  3. COption (c)

    Article 252

  4. DOption (d)

    Article 253

View answer & explanation

Correct answer

Answer: (d)D.

Article 253

Why this answer is correct

The correct answer is Article 253.

  • Article 253 of the Indian Constitution empowers Parliament to make laws for implementing international agreements.
  • Article 253- empowers Parliament to make any law for the whole or any part of the territory of India for implementing treaties, international agreements, and conventions.
  • It enables the Government of India to implement all international obligations and commitments.

Additional Information

  • Article 249- empowers the parliament to legislate with respect to a matter in the State List in the national interest.
  • Article 250- According to this parliament is empowered to make laws on any item that is included in the State List for the whole or part of India, while a Proclamation of emergency is in operation.
  • Article 252- It is about the Power of Parliament to legislate for two or more States by consent and adoption of such legislation by any other State.

Question 14

Match List-I with List-II and select the correct answer using the codes given below the lists:

List – I (Text)List-II (Author)
(A) Kiratarjuniyam1. Dandi
(B) Dashakumar Charitam2. Kalidas
(C) Buddha Charitam3. Bharavi
(D) Vikramorvashiyam4. Ashvagosha

Choose the correct option from those given below:

  1. AOption (a)

    (A) - (3), (B) - (4), (C) - (1), (D) - (2)

  2. BOption (b)

    (A) - (3), (B) - (1), (C) - (4), (D) - (2)

  3. COption (c)

    (A) - (2), (B) - (3), (C) - (1), (D) - (4)

  4. DOption (d)

    (A) - (1), (B) - (3), (C) - (2), (D) - (4)

View answer & explanation

Correct answer

Answer: (b)B.

(A) - (3), (B) - (1), (C) - (4), (D) - (2)

Why this answer is correct

The correct answer is (A) - (3), (B) - (1), (C) - (4), (D) - (2)​.

Key Points

  • Kiratarjuniyam- It is a Sanskrit epic written in the 6th century by Bharavi.
  • It is his only recognized work.
  • It is an epic poem with eighteen cantos in which Lord Shiva tests the power of Arjuna, one of the Pandavas in the Mahabharata.
  • Dashakumar Charitam-  It is authored by renowned Sanskrit poet Dandi.
  • It relates the adventures of ten princes in their pursuit of love and royal power.
  • Buddha Charitam-  It is an epic poem in the Sanskrit maha kavya style on the life of Gautam Budha by Ashvagosha, composed in the early second century.
  • Vikramorvashiya-  It is a five-act Sanskrit play by ancient Indian poet Kalidasa who flourished in the 4th Century CE, on the Vedic love story of king Pururavas and an Apsara, a celestial nymph named Urvashi.

Question 15

Who appoints the acting Chief Justice of India?

  1. AOption (a)

    Chief Justice of India

  2. BOption (b)

    Chief Justice of India with previous consent of the President

  3. COption (c)

    President of India

  4. DOption (d)

    President in consultation with the Chief Justice of India

View answer & explanation

Correct answer

Answer: (c)C.

President of India

Why this answer is correct

The correct answer is the President of India.

Key Points

  • The appointment of acting Chief Justice is to be made by the President under Article 126 of the Constitution.
  • Vacancy in the office of the Chief Justice must be filled whatever the period of vacancy.
  • Article 126 – Appointment of acting Chief justice.
  • Justice D Y Chandrachud is the current and 50th CJI.

Additional Information

Role of Chief Justice of India

 

  • The Chief Justice is responsible for the allocation of work to other judges.
  • The Chief Justice administers the oath of office to the President In the absence of the President and the Vice-President, the Chief Justice sits as the Acting President of India
  • The Chief Justice is the ex-officio Chancellor to most autonomous law schools in India.

Eligiblity

  • The individual must be a citizen of India.
  • The person must not exceed 65 years of age.
  • In order to be eligible to be Chief Justice of India, the person must serve as a judge at High Court for at least five years or the person should be an advocate in the High court or the Supreme court for at least 10 years or a distinguished jurist.

Question 16

The early farming site which is located on the bank of a lake is

  1. AOption (a)

    Mehargarh

  2. BOption (b)

    Laharadeva

  3. COption (c)

    Chirand

  4. DOption (d)

    T. Narsipur

View answer & explanation

Correct answer

Answer: (c)C.

Chirand

Why this answer is correct

The correct answer is Chirand​.

Key Points

  • Chirand is the early farming site located on the northern bank of the river Ganga together with two other rivers Sarayu and Son.
  • Chirand is an archaeological site in the Saran district of Bihar.
  • It is the first known site of the Neolithic age.
  • It has a large pre-historic mound (a rounded mass projecting above a surface) containing various artifacts.
  • The mound is known for its continuous archaeological record from the Neolithic age (about 2500–1345 BC) to the reign of the Pala Dynasty, which ruled this place during the pre-medieval period.
  • This is probably one of the youngest date of early farming known from the Gangetic basin.

Additional Information

  • T. Narsipur is a place located in the Mysore district in the Indian state of Karnataka.
  • This is the place in South India where Kumbhamela is held every three years.
  • The word 'Narasipura' is the name of the town, which is derived from the famous Gunja Narasimhaswamy temple that is located on the right bank of the Kabini river.

Question 17

The term ‘Office of profit’ has been defined by the

  1. AOption (a)

    Constitution

  2. BOption (b)

    Parliament

  3. COption (c)

    Supreme Court

  4. DOption (d)

    Union Council of Ministers

View answer & explanation

Correct answer

Answer: (a)A.

Constitution

Why this answer is correct

The correct answer is the Constitution.

Key Points

  • The term 'Office of profit' has not been directly defined by the Constitution.
  • But The Constitution of India, apart from enlisting certain qualifications for Members of Parliament and Legislative Assembly, also enumerates certain disqualifications. One of these disqualifications is holding an “office of profit”.
  • Under the provisions of Article 102 (1) and Article 191 (1) of the Constitution, an MP or an MLA (or an MLC) is barred from holding any office of profit under the central or state government.
  • The articles clarify that “a person shall not be deemed to hold an office of profit under the government of India or the government of any state by reason only that he is a minister”.
  • A person will be disqualified if he holds any office of profit under the central or state government, other than an office declared not to disqualify its holder by a law passed by Parliament or state legislature.

 Principles for including ‘office of profit’ as a criterion for disqualification are:

  • Makers of the Constitution wanted that legislators should not feel obligated to the Executive in any way, which could influence them while discharging legislative functions.
  • In other words, an MP or MLA should be free to carry out her duties without any kind of governmental pressure. The intent is that there should be no conflict between the duties and interests of an elected member.
  • The office of profit law simply seeks to enforce a basic feature of the Constitution- the principle of separation of power between the legislature and the executive.

Question 18

A large tank near Mahoba, temples at Ajaygarh and Mahoba and city of Rajavasini were built by a Chandella king_____.

  1. AOption (a)

    Nannuk

  2. BOption (b)

    Vakpati

  3. COption (c)

    Rahil

  4. DOption (d)

    Jayashakti

View answer & explanation

Correct answer

Answer: (c)C.

Rahil

Why this answer is correct

The correct answer is Rahil. 

 

  • A large tank near Mahoba, temples at Ajaygarh and Mahoba and the city of Rajavsini were built by Chandella King Rahil.
  • The town Rahilya which is three km southwest of Mohaba was named after Rahil.
  • The Chandela or Chandel is a Rajput clan in Central India.
  • An area of the Chandelas which was otherwise called Chandela Dynasty led a great part of the Bundelkhand district of central India for a long period of time between the 10th and the thirteenth century AD.
  • Chandel Dynasty is known in Indian history for Maharaja Rao Vidyadhara, who spurned the assaults of Mahmud of Ghazni.

Question 19

While deciding any question relating to the disqualification of a Member of Parliament, the President shall obtain the opinion of

  1. AOption (a)

    Election Commission

  2. BOption (b)

    Chief Justice of India

  3. COption (c)

    Attorney General

  4. DOption (d)

    Speaker of the Lok Sabha

View answer & explanation

Correct answer

Answer: (a)A.

Election Commission

Why this answer is correct

The correct answer is Election Commission.

  • While deciding any question relating to the disqualification of a Member of Parliament, the President shall obtain the opinion of the Election Commission.
  • Election Commission of India is a permanent Constitutional Body.
  • The Constitution provides for an independent election commission to ensure free and fair election to the Parliament, the State legislature,and the offices of President and Vice-President.
  • Consists of Chief Election Commissioner +2 Election Commissioners.
  • The Chief Election Commissioner is appointed by the President and the other Election Commissioners are appointed by the President after consultation with the Chief Election Commissioner, Article 324 also provides for the appointment of Regional Commissioners at the time of General Elections after consultation with the Election Commission.
  • Election Commissioners are appointed for a term of 6 years.
  • They are not eligible for re-appointment. Also, they cannot hold any office of profit after their retirement.
  • In article 324 of the Indian constitution, it envisages the Election Commission of India (ECI).

 

Additional Information

Chief Justice of IndiaThe Chief Justice of India (CJI) is the head of the judiciary of India and the Supreme Court of India. The CJI also heads the administrative functions of the judiciary.Current- Arvind Bobde
Attorney GeneralAttorney General of India is the chief legal advisor to the government of India and advises the union government on all legal matters. The Attorney General of India is the highest law officer in the countryCurrent- KK Venugopal
Speaker of the Lok SabhaThe Speaker of Lok Sabha is both a member of the House and its Presiding Officer. The Speaker conducts the business in the HouseCurrent- Om Birla

Question 20

Author of the ‘Dastane Mazahib’ which discusses about the Din-i-Ilahi of Akbar, was

  1. AOption (a)

    Mohammad Rabbani

  2. BOption (b)

    Mohsin Fanni

  3. COption (c)

    Badauni

  4. DOption (d)

    Afif

View answer & explanation

Correct answer

Answer: (b)B.

Mohsin Fanni

Why this answer is correct

The correct answer is Mohsin Fanni.

  • The author of the ‘Dastane Mazahib’ which discusses the Din-i-Ilahi of Akbar, was Mohsin Fanni.
  • Din-i Ilahi “the religion of God,” was a system of religious beliefs introduced by the Mughal emperor Akbar in 1582 CE.
  • Akbar's idea was to combine Islam and Hinduism into one faith, but also to add aspects of Christianity, Zoroastrianism, and Jainism.
  • Akbar took a deep personal interest in religious matters.
  • He founded an academy, the Ibadat Khana, “the House of Worship,” in 1575, where representatives of all major faiths could meet to discuss questions of theology.

​

 

Akbar

  • Akbar was born as Abu'l-Fath Jalal ud-din Muhammad Akbar on October 15, 1542.
  • Akbar succeeded his father, Humayun, in 1556 when he was 13 years old.
  • Akbar was given the nickname 'the Great' because of his many accomplishments.
  • Akbar started a new religion that was based on the teachings of major religions like Hinduism, Christianity, Zoroastrianism, etc.
  • This religious path was later referred to as the Din-i-illahi or Divine Monotheism.
  • Historian Vinset Smith called Akbar's Din-i-ilahi as a monument of his folly not of wisdom.

Question 21

Which of the following is not a Kharif crop?

  1. AOption (a)

    Soyabean

  2. BOption (b)

    Lentil

  3. COption (c)

    Cotton

  4. DOption (d)

    Bajra

View answer & explanation

Correct answer

Answer: (b)B.

Lentil

Why this answer is correct

The correct answer is Lentil.

  • Lentil is not a Kharif Crop among the given options.

Key Points

  • India has many growing seasons due to the prevalence of high temperatures over a long period. The different crop seasons are:​
  • Kharif Crop​
  • Crops are sown at the beginning of the southwest monsoon and harvested at the end of the South-West monsoon.
  • Sown in June-July when rains first begin.
  • Harvested in September-October.
  • Requires a lot of water and hot weather to grow.
  • Important crops: Jowar, Bajra, Soybean, Rice, Maize, Cotton, Jute, Groundnut, Sugarcane.
  • Rabi crop
  • Crops need a relatively cool climate during the period of growth but a warm climate during the germination of their seed and maturation.
  • Sown in October-November.
  • Harvested in April-May.
  • Important Crops: Wheat, Barley, Gram, Linseed, Mustard, Masur, Lentil and Potatoes, Tobacco.

Question 22

Which of the following Rights a cultivator enjoyed on his own land during the Mughal period?

  1. AOption (a)

    Right to mortgage only

  2. BOption (b)

    Right to sell and gift

  3. COption (c)

    Right to mortgage and gift

  4. DOption (d)

    All the above rights

View answer & explanation

Correct answer

Answer: (c)C.

Right to mortgage and gift

Why this answer is correct

The correct answer is Right to mortgage and gift.

 

  • Cultivators during the Mughal period enjoyed the Right to mortgage and gift their land.
  • The Mughal dynasty was founded by Babur.
  • He was a Chagatai Turkic prince and was descended from the Turkic conqueror Timur (Tamerlane) on his father’s side and Genghis Khan, on his mother’s side.
  • The Mughal period was between 1526-1857.
  • Mughal Empire controlled almost the entire Indian subcontinent.
  • It stretched from the edges of the Indus river basin, northern Afghanistan and Kashmir in the north west to the now-Assam and Bangladesh highlands in the east, and down to the uplands of Deccan plateau in the south.

Question 23

Soyabean seed contains

  1. AOption (a)

    20% protein and 40% oil

  2. BOption (b)

    40% protein and 10% oil

  3. COption (c)

    40% protein and 20% oil

  4. DOption (d)

    20% protein and 20% oil

View answer & explanation

Correct answer

Answer: (c)C.

40% protein and 20% oil

Why this answer is correct

The correct answer is 40% protein and 20% oil.

Key Points

  • Soybean seeds contain 40% of crude protein and about 20% of fat.
  • The soybean is one of the most economical and valuable agricultural commodities because of its unique chemical composition.
  • Since time immemorial, Soyabean has served as meat, milk, cheese, bread as well as oil for people across the globe.
  • Soyabean is India’s one of the fastest-growing crops and a significant foreign exchange earner.

Question 24

Who was appointed the Minister of ‘Ministry of Rehabilitation’ set up on 06 September, 1947?

  1. AOption (a)

    S. P. Mukerji

  2. BOption (b)

    Sardar Vallabhabhai Patel

  3. COption (c)

    J. L. Nehru

  4. DOption (d)

    K. C. Niyogy

View answer & explanation

Correct answer

Answer: (d)D.

K. C. Niyogy

Why this answer is correct

The correct answer is KC Niyogi.

Key Points

  • KC Niyogi was appointed the Minister of 'Ministry of Rehabilitation' set up on 6 September 1947.
  • Kshitish Chandra Neogy (1888–1970), also known as KC Neogi, was an Indian politician from West Bengal.
  • He was a member of the Constituent Assembly of India, a member of the first Cabinet of independent India, and the chairman of the first Finance Commission of India.
  • Neogy was elected as a member of the Constituent Assembly of India and after independence became a member of the First Cabinet of Independent India under Jawaharlal Nehru as the Minister of Relief and Rehabilitation and later as Minister for Commerce.

Question 25

The rotation intensity of Maize – Mustard – Mung crop is

  1. AOption (a)

    100%

  2. BOption (b)

    200%

  3. COption (c)

    300%

  4. DOption (d)

    400%

View answer & explanation

Correct answer

Answer: (c)C.

300%

Why this answer is correct

The correct answer is 300%.

 

  • Crop intensity is referred to as the number of crops grown in the same field in one agriculture year.
  • The formula to calculate any crop intensity is:
  • ​Crop intensity= Total cropped area / Total sown Area)X100
  • ​In this case, the number of different crops is 3.
  • So, here the rotation intensity of Maize – Mustard – Mung crop is 300%.

Technical (100 questions)

Question 26

 An irrigation channel designed by Lacey’s theory has a mean velocity of 1.5 m/s. The silt factor is unity. The hydraulic mean radius will be:

  1. AOption (a)

    2.5 m 

  2. BOption (b)

    1.5 m

  3. COption (c)

    5.625 m

  4. DOption (d)

    6.525 m

View answer & explanation

Correct answer

Answer: (c)C.

5.625 m

Why this answer is correct

Concept:

As per Lacey’s theory-

Hydraulic radius (R) is given by,

  R=52V2fR =\frac{5}{2}\frac{{{{\rm{V}}^2}}}{{\rm{f}}}

 Where,

 V is the flow velocity

 f is silt factor

Calculation:

 Given,

 v = 1.5 m/s, f = 1

Hydraulic mean radius,

  R=52×V2f=52×1.521R =\frac{5}{2} \times \frac{{{{\rm{V}}^2}}}{{\rm{f}}} = \frac{5}{2} \times \frac{{{1.5^2}}}{1} 

 = 5.625 m

Important Points

Following relations are used in Lacey's Theory

The velocity of flow is given by V = (Qf2140)16{\left( {\frac{{Q{f^2}}}{{140}}} \right)^{\frac{1}{6}}}

Where,

f = silt factor = 1.76√d and d = average size of soil particles in mm.

Q is discharge , Area of the section is given by A = Q/V

Perimeter is given by, P = 4.75√Q

Bed slope(S), is given by S = F533340Q16\frac{{{{\rm{F}}^{\frac{5}{3}}}}}{{3340{{\rm{Q}}^{\frac{1}{6}}}}}

Question 27

In a hydraulic jump, the depths on the two sides are 0.4 in and 1.4 m. The head loss in the jump is nearly

  1. AOption (a)

    0.45 m

  2. BOption (b)

    0.65 m

  3. COption (c)

    0.80 m

  4. DOption (d)

    0.90 m 

View answer & explanation

Correct answer

Answer: (a)A.

0.45 m

Why this answer is correct

Concept:

Hydraulic jump: Whenever supercritical flow merges into a subcritical flow, a sudden jump is formed to reduce the energy of the water depth, is known as a hydraulic jump.

For a rectangular channel, energy loss is given as:

\({{Δ E}}=\frac{{{\left( {{\text{Y}}{2}}-{{\text{Y}}{1}} \right)}^{3}}}{4{{\text{Y}}{1}}{{\text{Y}}{2}}}\)

Here,  

Y2 = post jump depth, and Y1 = pre-jump depth

Efficiency of jump=Actual energy loss in jumpRequired energy loss in jump×100\text{Efficiency of jump}=\frac{\text{Actual energy loss in jump}}{\text{Required energy loss in jump}}\times 100

Calculation:

Head loss during a hydraulic jump

ΔE=(y2−y1)34y1y2{\rm{Δ }}E = \frac{{{{\left( {{y_2} - {y_1}} \right)}^3}}}{{4{y_1}{y_2}}}

where y1 = pre-jump depth and y2 = post-jump

∴ ΔE = 0.45 m

Question 28

The contact pressure PC, tyre pressure P, and rigidity factor R are related by

  1. AOption (a)

    PPC=R\frac{{\rm{P}}}{{{{\rm{P}}_{\rm{C}}}}} = {\rm{R}}

  2. BOption (b)

    PCP=R\frac{{{{\rm{P}}_{\rm{C}}}}}{{\rm{P}}} = {\rm{R}}

  3. COption (c)

    P × PC = R

  4. DOption (d)

    R=;(P×PC){\rm{R}} = {\rm{;}}\sqrt {\left( {{\rm{P}} \times {{\rm{P}}_{\rm{C}}}} \right)}

View answer & explanation

Correct answer

Answer: (b)B.

PCP=R\frac{{{{\rm{P}}_{\rm{C}}}}}{{\rm{P}}} = {\rm{R}}

Why this answer is correct

Explanation:

(i) The ratio of contact pressure to tyre pressure is defined as the rigidity factor.

Rigidity factor = Contact pressure (Pc)/Tyre pressure (P)

R = Pc/P

Contact pressureTyre pressureRigidity factor
7 kg/cm27 kg/cm21
> 7 kg/cm2< 7 kg/cm2> 1
< 7 kg/cm2> 7 kg/cm2< 1

Where,

Contact pressure = Load on wheel/Contact area

Tyre pressure = Pressure inside the tyre

(ii) Rigidity factor shows degree of tension developed in the tyre. When tyre pressure is low, walls of the tyre are subjected to compression and when tyre pressure is high walls are subjected to tension.

(iii) Tyre pressure is effective in surface layer while contact pressure is effecting throughout the thickness of the pavement i.e. thickness of pavement is affected by contact pressure, not by tyre pressure but contact pressure depends on tyre pressure.

Question 29

If modulus of elasticity of the subgrade is 25 MPa, then deflection at the surface of flexible pavement due to a wheel load of 40 kN and a tyre pressure of 0.6 MPa will be:

  1. AOption (a)

    5.24 mm

  2. BOption (b)

    6.55 mm

  3. COption (c)

    7.40 mm

  4. DOption (d)

    8.32 mm

View answer & explanation

Correct answer

Answer: (a)A.

5.24 mm

Why this answer is correct

Concept:

Burmister’s Method:

Assumptions

  • Materials in each layers are isotropic, homogeneous and elastic.
  • Pavement forms a stiffer layer having higher value of E than that of subgrade.
  • Layers are in constant contact.
  • Surface layer is infinite in horizontal direction but finite in vertical direction.

This method gives the following design deflection values for pavements with different layers –

  1. For flexible pavement –

Δ=1.5paEs×F2\Delta = 1.5\frac{{pa}}{{{E_s}}} \times {F_2}

  1. For rigid pavement –

Δ=1.18paEs×F2\Delta = 1.18\frac{{pa}}{{{E_s}}} \times {F_2}

Where, p = contact pressure at road surface due to wheel load (kg/m2)

 Es = modulus of elasticity of subgrade (kg/cm2),

 a = radius of contact area(cm) and

 F2 = deflection factor which depends upon Es/EP  and h/a,  for single layer system F2 = 1.

Formula used:-

Design deflection for single-layered flexible pavement is given by,

Δ=1.5paEs\Delta = 1.5\frac{{pa}}{{{E_s}}}

Radius of contact area is given by,

a=(Pp)×1πa = \sqrt {\left( {\frac{P}{p}} \right) \times \frac{1}{\pi }}

Calculation:

Wheel Load, P = 40 kN

Modulus of elasticity for subgrade and pavement, ES = EP = 25 MPa

Tyre pressure, p = 0.60 MPa

 Radius of contact (a) 

a=(Pp)×1π⇒a=40×1030.6×106×13.14=0.14567ma = \sqrt {\left( {\frac{P}{p}} \right) \times \frac{1}{\pi }} \Rightarrow a = \sqrt {\frac{{40 \times {{10}^3}}}{{0.6 \times {{10}^6}}} \times \frac{1}{{3.14}}} = 0.14567 m

Design deflection for flexible pavement

Δ;=1.5paEs\Delta ; = 1.5\frac{{pa}}{{{E_s}}}

⇒Δ;=1.5×0.6×0.145725=0.005244m;≈5.244mm; \Rightarrow \Delta ; = 1.5 \times \frac{{0.6 \times 0.1457}}{{25}} = 0.005244 m; \approx 5.244mm;

Question 30

The design speed of traffic lane is 70 kmph. What is the theoretical capacity per hour taking the total reaction time to be 2 seconds and average length of the vehicles as 8 m?

  1. AOption (a)

    828

  2. BOption (b)

    728

  3. COption (c)

    628

  4. DOption (d)

    428

View answer & explanation

Correct answer

Answer: (b)B.

728

Why this answer is correct

Concept:

Maximum theoretical capacity on the basis of space headway:

Theoretical capacity of a lane, C=1000VSC = \frac{{1000V}}{S}

where, C = Capacity of single lane (vehicle per hour)

V = Speed of vehicle (kmph)

S = Average center to center spacing of vehicles = SSD + L

SSD = Stopping sight distance

L = Average length of vehicle

Calculation:

Design speed, V = 70 km/hr = 19.44 m/sec

Total reaction time, t = 2 sec

The average length of the vehicle, l = 8 m

Theoretical capacity per hour, C=1000;VSC = \frac{{1000;V}}{S}

S = average centre to centre spacing between vehicles

S =((0.278 ×V ×t) + (V2254 ×f)) + 8 = ((0.278\ \times V\ \times t)\ +\ (\frac{V^2}{254\ \times f}))\ +\ 8

S =((0.278 ×70 ×2) + (702254 ×0.36)) + 8 = ((0.278\ \times 70\ \times 2)\ +\ (\frac{70^2}{254\ \times 0.36}))\ +\ 8

S = 100.5 m

∴C=1000×70100.5=696.5;veh/hr\therefore C = \frac{{1000×70}}{{100.5}} = 696.5;veh/hr

So, the Nearest correct option is b.

Question 31

Calculate the stopping sight distance, given that velocity v = 100 kmph and friction f = 0.10.

  1. AOption (a)

    464 m

  2. BOption (b)

    563 m

  3. COption (c)

    860 m

  4. DOption (d)

    840 m

View answer & explanation

Correct answer

Answer: (a)A.

464 m

Why this answer is correct

Concept:

Stopping Sight Distance:

(i) Stopping sight distance is the minimum distance over which the driver travelling at design speed can apply brakes and bring the vehicle to stop position safely without collision with any other obstruction.

(ii) It is also known as minimum sight distance or non passing sight distance. Stopping sight distance should be provided throughout the length of all roads.

(iii) Stopping sight distance composed of two components:

(a) Lag distance: It is the distance travelled by the vehicle in total reaction time if v is the design speed in m/s and t is the total reaction time in sec, then

lag distance = vt meters

t = total reaction time = 2.5 second (As per IRC)

(b) Braking distance: It is the distance travelled by vehicle after the application of brakes.

Braking distance, L=v22gfL = \frac{{{v^2}}}{{2gf}}

Where, v =  design speed of vehicle in m/s

f = Coefficient of friction

Therefore,

Stopping sight distance (SSD) = Lag distance + Braking distance

SSD = vt+v22gfvt + \frac{{{v^2}}}{{2gf}}

Calculation:

Given, v = 100 kmph = 100/3.6 = 27.78 m/s , (1 kmph = 1/3.6 m/s)

f = 0.10

t = 2.5 second (As per IRC)

SSD=vt+v22gf=27.78×2.5+27.7822;×;9.81;×;0.10SSD = vt + \frac{{{v^2}}}{{2gf}} = 27.78 \times 2.5 + \frac{{{{27.78}^2}}}{{2; \times ;9.81; \times; 0.10}}

SSD = 462.78 m

So as per given option most appropriate answer is 464 m

Question 32

The following items are considered for the selection of a site for an airport. Mark the incorrect option.

  1. AOption (a)

    Class of airport

  2. BOption (b)

    Visibility at airport site

  3. COption (c)

    Altitude

  4. DOption (d)

    Runway orientation

View answer & explanation

Correct answer

Answer: (a)A.

Class of airport

Why this answer is correct

Explanation:

The selection of a suitable site for an airport depends upon the class of airport under consideration. However, if such factors as required for the selection of the largest facility are considered the development of the airport by stages will be made easier and economical. The factors listed below are for the selection of a suitable site for a major airport installation:

(i) Regional plan

(ii) Airport use

(iii) Proximity to other airports

(iv) Ground accessibility

(v) Topography

(vi) Obstructions

(vii) Visibility

(viii) wind

(ix) Noise nuisance

(x) Grading, drainage and soil characteristics

(xi) Future development

(xii) Availability of utilities from town

(xiii) Economic consideration

(xiv) Runway orientation

Question 33

The order in which a road is built as from bottom to top:

  1. AOption (a)

    subsoil, base, subgrade, sub base

  2. BOption (b)

    base, subsoil, subgrade, sub base

  3. COption (c)

    subbase, base, subgrade, subsoil

  4. DOption (d)

    subsoil, subgrade, subbase, base

View answer & explanation

Correct answer

Answer: (d)D.

subsoil, subgrade, subbase, base

Why this answer is correct

Explanation:

Types of pavement structure:

Pavements are generally classified into two categories based on structural behavior:

(i) Flexible pavement

(ii) Rigid pavement

Flexible pavement:

(i) The pavements which have very less flexural strength are called flexible pavements.

(ii) This type of pavements transmit the load to the lower layer by grain to grain transfer.

(iii) A typical flexible pavement consists of four components as shown in the figure below

  • Soil subgrade
  • Sub-base course
  • Base course
  • Surface course

Rigid pavement:

(i) Rigid pavement are those which possess worthy flexural strength.

(ii) The rigid pavement transmits the wheel load stresses through a wider area below by the slab action.

Important point:

(i) IRC–37:2012 Design code for the design of flexible pavement.

(ii) Flexible pavement are commonly designed using empirical charts or equations.

(iii) IRC-58:2012  Design code for the design of rigid pavement.

(iv) Rigid pavements are designed using elastic theory

Question 34

A vehicle moving at 50 km/h speed was stopped by applying brakes and the length of the skid marks was 18 m. If the average skid resistance of the pavement is 0.75, the brake efficiency (in %) of the test vehicle will be

  1. AOption (a)

    71.12%

  2. BOption (b)

    72.83%

  3. COption (c)

    73.48%

  4. DOption (d)

    74.62%

View answer & explanation

Correct answer

Answer: (b)B.

72.83%

Why this answer is correct

Concept:

Braking distance:

(i) It is the distance travelled by vehicle after the application of brakes.

(ii) It is obtained by equating the work done in stopping the vehicle and kinetic energy stored in the vehicle.

Let us consider, F is the maximum frictional force developed and L is the braking distance, then the work done against friction in stopping the vehicle will be F × L.

Where, frictional force, F = f × W

Where W is the total weight of vehicle and f is the coefficient of friction

So, work done in stopping the vehicle = f × WL

While the kinetic energy stored in vehicle = 12mv2=12Wv2g\frac{1}{2}m{v^2} = \frac{1}{2}\frac{{W{v^2}}}{g}  (∵ W = mg)

Now by using the law of conservation of energy,

Work done in stopping the vehicle = Kinetic energy stored in the vehicle

fWL=12Wv2gfWL = \frac{1}{2}\frac{{W{v^2}}}{g}

L=v22gfL = \frac{{{v^2}}}{{2gf}}

Braking distance, L=v22gfL = \frac{{{v^2}}}{{2gf}}

If the braking efficiency is η,

Braking distance, L=v22gfηL = \frac{{{v^2}}}{{2gf\eta }}

Calculation:

Given,

v = 50 kmph = 50/3.6 = 13.89 m/s  (∵ 1 kmph = 1/3.6 m/s)

L = 18 m

f = 0.75

∵ we know that, braking distance, L=v22gfηL = \frac{{{v^2}}}{{2gf\eta }}

18=13.8922;×;9.81;×;0.75;×;η18 = \frac{{{{13.89}^2}}}{{2; \times ; 9.81; \times ;0.75; \times ;\eta }}

η = 0.7284 = 72.84 %

Question 35

For a sleeper density of (n + 5) the number of sleepers required for constructing a Broad Gauge (B.G.) railway track of length 650 m is given by

  1. AOption (a)

    1000

  2. BOption (b)

    900

  3. COption (c)

    800

  4. DOption (d)

    700

View answer & explanation

Correct answer

Answer: (b)B.

900

Why this answer is correct

Concept

Sleeper density is denoted by (n + x)

These vary from (n+3) to (n+6)

Where ‘n’ is the length of one rail

Generally length of one rail (n) = 13 m (Need to remembered)

Calculation

Given,

 Length of rail = 650 m

 For BG track, length of rail = 13 m

 Number of rails =65013=50= \frac{{650}}{{13}} = 50 

 Sleeper Density = n + 5

 Number of sleepers per rail length = 13 + 5 = 18

 So number of sleepers needed = Number of rails × Sleeper density

 = 50× 18 = 900 

 ∴ Number of sleepers need = 900

Question 36

The type of the camber which is best suited for the cement concrete pavement is

  1. AOption (a)

    Straight line

  2. BOption (b)

    Parabolic

  3. COption (c)

    Elliptical

  4. DOption (d)

    Composite

View answer & explanation

Correct answer

Answer: (a)A.

Straight line

Why this answer is correct

Explanation:

Camber:

  • Camber is the slope provided in the transverse direction of the road to drain off the rainwater from the road surface.
  • Usually, a camber is provided in the straight roads by raising the center of the carriageway with respect to the edges forming the highest point at the center.
  • The straight slope of the camber is easier to be cast and maintained in the case of concrete pavement.
  • Parabolic shaped camber is difficult to construct and maintain. It has steeper edges which are inconvenient to use. However, it is kept in bituminous pavements for better drainage of water.

 

PavementShape of camber
Cement concrete pavementStraight
Bitumen pavementParabolic

Question 37

Which one is NOT a road pattern?

  1. AOption (a)

    Block pattern

  2. BOption (b)

    Star and block pattern

  3. COption (c)

    Hexagonal pattern

  4. DOption (d)

    Diamond pattern

View answer & explanation

Correct answer

Answer: (d)D.

Diamond pattern

Why this answer is correct

Explanation:

The various road patterns may be classified as follows:

(a) Rectangular or block pattern

(b) Radial or star and block pattern

(c) Radial or star and circular pattern

(d) Radial or star and grid pattern

(e) Hexagonal pattern

Important points:

(i) The rectangular pattern has been adopted in the city roads of Chandigarh

(ii) Radial and circular pattern is the road network of Cannaught Place in New Delhi

Question 38

If methyl orange alkalinity of water equals or exceeds total hardness, all of the hardness is:

  1. AOption (a)

    Non-carbonate hardness

  2. BOption (b)

    Carbonate hardness

  3. COption (c)

    Pseudo hardness

  4. DOption (d)

    Negative non-carbonate hardness

View answer & explanation

Correct answer

Answer: (b)B.

Carbonate hardness

Why this answer is correct

Concept:

Alkalinity is defined as ability of water to neutralize the acid.

Major constituents are CO32- and HCO3 –

and Minor constituent is OH-

[OH-] is negligible so we don’t consider in calculation  

Hardness of water is defined as the concentration of multivalent metallic cations which destroy the surfaced property of soap (Concentration of ions) which reacts with Soap and leads to the formation of a precipitate.

Ca 2+, Mg2+ are major constituents

Hardness is categorized into 2

Carbonate hardness and non-carbonate hardness

a) If TH > TA

Then, CH = TA

b) If TH ≤ TA

Then CH = TH

 As in the question it is mentioned if methyl alkalinity exceeds Total Hardness then all of the hardness is carbonate Hardness

Note:

The relative quantity of alkalinity species are pH-dependent. It is obtained using a titration curve.

The titration curve is plotted by taking measurement of pH at every stage.

  • The conversion of CO32-  to HCO3-  is essentially complete at pH = 8.3, but  HCO3- formed also requires acid. Hence it is thought that half of CO32-  have been neutralized up to pH = 8.3.
  • The neutralization of OH- is completed up to pH = 8.3. Hence (OH−+12CO32−)\left( {O{H^ - } + \frac{1}{2}CO_3^{2 - }} \right) alkalinity is completely neutralized up to pH = 8.3
  • At pH = 4.5 all the bicarbonates are neutralized. Hence, the amount of acid required to titrate a sample of water to pH = 4.5 is equivalent to the total alkalinity of water.

P = Phenolphthalein alkalinity

M = Methyl orange alkalinity

  • If P = M all alkalinity is caustic alkalinity.
  • If P = M/2, all alkalinity is carbonate alkalinity.
  • If P < M/2, predominant species are carbonate and bicarbonate.
  • If P > M/2, the predominant species are carbonate and Hydroxide.
  • If P = 0 total alkalinity is bicarbonate alkalinity

Question 39

When waste water is disposed of into a running stream, four zones are formed. In which one of the following zones will the minimum level of dissolved oxygen be found?

  1. AOption (a)

    Zone of degradation

  2. BOption (b)

    Zone of active decomposition

  3. COption (c)

    Zone of recovery

  4. DOption (d)

    Zone of clear water

View answer & explanation

Correct answer

Answer: (b)B.

Zone of active decomposition

Why this answer is correct

Explanation

Correct order is

Zone A – Zone of clear water

Zone B – Zone of Degradation

Zone C – Zone of Active decomposition

Zone D – Zone of Recovery

Zone E – Zone of recovery

From the curve, we can say in the zone of active decomposition there is a minimum level of dissolved oxygen.

ZONES OF POLLUTION: A polluted stream undergoing self-purification presents the following four distinct zones of pollution

(1) ZONES OF DEGRADATION: This usually occurs below the output sewer when discharging its contents into the stream. The zone is characterized by water becoming dark and turbid with the formation of sludge deposits on the bottom. Dissolved oxygen gets reduced to 40%.

(2) ZONES OF ACTIVE DECOMPOSITION: This is marked by heavy pollution. It is characterized by the absence of dissolved oxygen; water is grayish and darker with active anaerobic organic decomposition accompanying and with the evolution of methane (CH4), Hydrogen sulphide (H2S), Carbon dioxide (CO2) and Nitrogen (N2), bubbling to the surface with masses of sludge forming black scum. Fish life is practically absent, fungi and bacteria disappear. As the organic decomposition slackens, reaction sets in and D.O. again rises to its original level (i.e. 40%).

(3) ZONE OF RECOVERY: In this zone, the stream tries to recover its former appearance. Most of the organic matter has been settled as sludge, B.O.D. falls and the D.O. content rises above 40% microscopic aquatic life reappears. Water becomes clearer, fungi decrease and algae reappear. Mineralization is active and products such as nitrates, sulphates, and carbonates are formed.

(4) CLEAR WATER ZONE: In this, the natural stream condition is restored, the D.O. is higher than the BOD. Oxygen balance is attained and recovery is said to be complete. Water becomes attractive in appearance. Some pathogenic organisms may, however, be present.

Question 40

Hairs of human nose can remove all the particles of size greater than

  1. AOption (a)

    1 micron

  2. BOption (b)

    10 micron

  3. COption (c)

    100 micron

  4. DOption (d)

    None of these

View answer & explanation

Correct answer

Answer: (b)B.

10 micron

Why this answer is correct

Explanation:

(i) The function of the fine hair inside our nose is to keep foreign or unwanted particles away from entering the lungs through the nasal cavity.

(ii) The function of mucus inside our nose is it aids in moisturizing the inhaled air and prevents tissues such as the nasal and the airway epithelia from drying out.

(iii) Particles that are 10 microns or less are considered respirable and can settle deep into the lungs often causing adverse health effects. So Hairs of human nose can remove all the particles of size greater than 10 micron.

Question 41

Match List - I with List-II and select the correct answer using the codes given below the lists:

List - I (Treatment Unit)List - II (Detention Time)
A. Grit chamberi. Six hours
B. Primary sedimentationii. Two minutes
C. Activated sludgeiii. Two hours
D. Sludge digestioniv. Twenty days
  1. AOption (a)

    A - iii, B - i, C - iv, D - ii

  2. BOption (b)

    A - ii, B - iii, C - i, D - iv

  3. COption (c)

    A - ii, B - i, C - iii, D - iv

  4. DOption (d)

    A - i, B - ii, C - iii, D - iv

View answer & explanation

Correct answer

Answer: (b)B.

A - ii, B - iii, C - i, D - iv

Why this answer is correct

Explanation:

Detention time for different type of Treatment unit

Treatment UnitDetention time
Grit chamber30-60 second
Primary sedimentation2-2.5 hour
Sludge digestion20-30 days
Activated sludge process2-4 hour
Oxidation pond2-6 weeks
Septic tank12-36 hour

 

Note: Septic tank has high detention time whereas Grit chamber has less detention time.

Question 42

The best system for distribution of water in a randomly planned city is:

  1. AOption (a)

    Dead end system

  2. BOption (b)

    Grid iron system

  3. COption (c)

    Ring system

  4. DOption (d)

    Radial system

View answer & explanation

Correct answer

Answer: (a)A.

Dead end system

Why this answer is correct

Explanation

Dead-end System:

  • It is also called a tree system, it consists of one main supply line, from which originates (generally at right angles) a number of sub-main pipes; Each sub-main is then divided into several branch pipes, called laterals
  • This type of distribution system is suitable for older towns which have developed in a haphazard manner, without properly planned road e.g. old city, irregularly grown city, etc; It is economical and simple

Gridiron System:

  • It is also known as an interlaced system or reticulation system, the mains, sub-mains, and branches are all connected with each other
  • There is no dead-end in the system as looping is provided and is most suitable for well-planned cities; There is equal pressure in all pipe and multiple flow path

Radial system:

  • If a city or town is having a system of radial roads emerging from different centers, the pipeline can be best laid in a radial method by placing the distribution reservoir at these centers
  • The water from the distribution reservoir is then supplied radially to distribution pipes and thus also known as zonal distribution

Ring System:

  • It is also called a circular system; In this system, a closed ring, either circular or rectangular, of the main pipes, is formed around the area to be served; The distribution area is divided into rectangular or circular blocks, and the main water pipes are laid on the periphery of the blocks
  • This system is very suitable for towns and cities having well-planned roads; It is economical and pressure at the ends are reasonably equal

Question 43

The shape of transition curve used by Indian Railway is

  1. AOption (a)

    Euler’s Spiral

  2. BOption (b)

    Cubic parabola

  3. COption (c)

    Sine curve

  4. DOption (d)

    Bernoulli's lemniscate

View answer & explanation

Correct answer

Answer: (b)B.

Cubic parabola

Why this answer is correct

The Railway Board has decided that on Indian Railways, transition curves will normally be laid in the shape of a cubic parabola.

  • In this curve, both the curvature and the cant increase at a linear rate
  • The cant of the transition curve from the straight to the curved track is so arranged that the inner rail continues to be at the same level while the outer rail is raised in the linear form throughout the length of the curve
  • A straight-line ramp is provided for such transition curves

Question 44

The Govt. of India, appointed the National Transport Policy Committee in the year:

  1. AOption (a)

    1978

  2. BOption (b)

    1973

  3. COption (c)

    1956

  4. DOption (d)

    1943

View answer & explanation

Correct answer

Answer: (a)A.

1978

Why this answer is correct

Explanation

A conference of the chief engineers of all the states and provinces was convened in 1943 by the government of India at Nagpur, at the initiative of the Indian Roads Congress to finalize the first road development plan for the country as a whole.

This is the landmark in the history of road development in India, as it was the first attempt to prepare a coordinated road development programme in a planned manner. At the end of this plan, the target road length aimed at was 16 km per 100 square km area of the country.

The first 20-year plan is also known as the Nagpur road plan. It classified the roads in India based on location and function into the following five categories:

  1. National Highways
  2. State Highways
  3. Major District roads
  4. Other District roads
  5. Village Roads.

While National Transport Policy committee is appointed by the government of India in the year 1978 to prepare a national transport policy for the country for the next decade.

Question 45

Flexible pavement distributes the wheel load -

  1. AOption (a)

    through structural action

  2. BOption (b)

    through a set of layers grain by grain

  3. COption (c)

    directly to sub-grade

  4. DOption (d)

    ​none of the above

View answer & explanation

Correct answer

Answer: (b)B.

through a set of layers grain by grain

Why this answer is correct

Flexible pavements: Flexible pavements are so named because the total pavement structure deflects, or flexes, under loading. Flexible pavement distributes the wheel load through a set of layers grain by grain.

Flexible pavement may be constructed in a number of layers and the top layer has to be of the best quality to sustain maximum compressive stress, in addition, to wear and tear. The lower layers will experience the lesser magnitude of stress and low-quality material can be used.

Question 46

 The total correction for elevation temperature and gradient for a runway, should NOT be more than:

  1. AOption (a)

    35%

  2. BOption (b)

    25%

  3. COption (c)

    15%

  4. DOption (d)

    10%

View answer & explanation

Correct answer

Answer: (a)A.

35%

Why this answer is correct

Concept:

Correction for basic Runway length (l)

i) Correction for elevation

ICAO recommends that basic runway length should be increased at the rate of 7% per 300 m rise in elevation above mean sea level.

∴ Correction for elevation =7100×runway;length×Airport;elevation300 = \frac{7}{{100}} \times runway;length \times \frac{{Airport;elevation}}{{300}}

ii) Temperature correction

Airport reference Temperature (ART)

\({\rm{T}} = {{\rm{T}}{\rm{a}}} + \frac{{{{\rm{T}}{\rm{m}}} - {{\rm{T}}_{\rm{a}}}}}{3}\)

Tm → monthly mean of maximum daily temp of hottest month

Ta → monthly mean of the average daily temp of the hottest month

Rise in temperature = ART - SAT  

Where,

ART is Atmospheric reference temperature

SAT Standard atmospheric Temperature

As per ICAO, Basic runway length after correction for elevation should be further increased at the rate of 1% for every 1° C rise of the airport reference temperature

 correction for temperature =Correctedlength×1100×Rise;in;temperature= Correctedlength \times \frac{1}{{100}} \times Rise;in;temperature

Note: As per ICAO, the cumulative connection for elevation and temperature together should not be ≯ 35%.

Cumulative (%) correction =l2−l1l×100≯35%= \frac{{{{\rm{l}}_2} - {{\rm{l}}_1}}}{{\rm{l}}} \times 100 \not > 35\%

If exceeds modify, l2 = 1.35 × l

iii) Gradient correction

For every 1% effective gradient, runway length will be increased by 20%

\({\rm{Final;length;}}\left( {{{\rm{l}}_3}} \right) = {{\rm{l}}2} + \left( {20 \times \frac{{{{\rm{G}}{{\rm{effective}}}}}}{{100}}{\rm{% }}} \right){{\rm{l}}_2}\)

\({{\rm{G}}{{\rm{effective}}}}\left( {\rm{% }} \right) = \frac{{{\rm{R}}{{\rm{L}}{{\rm{highest;point}}}} - {\rm{R}}{{\rm{L}}_{{\rm{lower;point}}}}}}{{{\rm{Runway;unit;}}\left( {{{\rm{l}}_2}} \right)}}\).

Question 47

The population of the town of three consecutive years is 5000, 7000 and 8400 respectively. The population of the town in the fourth consecutive year according to the geometrical increase method is

  1. AOption (a)

    9500

  2. BOption (b)

    9800

  3. COption (c)

    10920

  4. DOption (d)

    11146

View answer & explanation

Correct answer

Answer: (d)D.

11146

Why this answer is correct

Concept:

Geometric incremental method:

This method is suitable for young and rapidly developing cities as they record logarithmic or exponential increases in population.

If population increase is given per decade:

Population after n decades (Pn) is given by

Pn=Po×(1+r100)n{{\rm{P}}_{\rm{n}}} = {P_o} \times {\left( {1 + \frac{r}{{100}}} \right)^n}

If the population increase is given per year:

\({{\rm{P}}{\rm{t}}} = {{\rm{P}}{\rm{o}}} \times {e^{\left( {\frac{k}{{100}} \times t} \right)}}\)

where,

Pn → Population after ‘n’ number of decades

Pt → Population after ‘t’ number of years

Po → Initial population considered

n → number of decades

t → number of years

r → geometric rate constant per decade

k → geometric rate constant per year

Calculation:

\({{\rm{P}}{\rm{t}}} = {{\rm{P}}{\rm{o}}} \times {e^{\left( {\frac{k}{{100}} \times t} \right)}}\)

YearPopulationIncrease% increase
1st year5000
2nd year7000200040
3rd year8400140020
4th year

 

Since given data is in increase per year:

Geometric rate constant per year (k) = 0.20×0.4\sqrt {0.20 \times 0.4}  = 0.2828 = 28.28%

Pt=8400×e(0.2828×1)=11145.93;≈11146{{\rm{P}}_{\rm{t}}} = 8400 \times {e^{\left( {0.2828 \times 1} \right)}} = 11145.93; \approx 11146

Confusion Points

If the population increase is given per year: Exponential method is used

If population increase is given per decade: Geometric increase method is used

Question 48

Water sample of pH = 4 when compared to sample of pH = 7, will be more acidic by:

  1. AOption (a)

    3 times

  2. BOption (b)

    300 times

  3. COption (c)

    1000 times

  4. DOption (d)

    None of these

View answer & explanation

Correct answer

Answer: (c)C.

1000 times

Why this answer is correct

Concept

We know, pH is defined as the negative logarithm of [H]+ ion.

So, 

pH = -log10 [H+]

-log10 [H+] = pH

[H+] = 10 -pH

Calculation

 pH of water samples are 

 pH = 4 ⇒[H+] = 10 - 4

 pH = 7 ⇒ [H+] = 10-7 

Comparing Both [H+]

\(\frac{{{{\left[ {{H^ + }} \right]}I}}}{{{{\left[ {{H^ + }} \right]}{II}}}} = \frac{{{{10}^{ -4}}}}{{{{10}^{ - 7}}}} = {10^{3}} = 1000\)

Hence, first sample is 1000 times acidic than second sample.

Question 49

One litre of sewage when allowed to settle for 30 minutes gives a sludge volume of 30 cm3. If the dry weight of this sludge is 3.0 gms, then the sludge volume Index will be:

  1. AOption (a)

    20 g/L

  2. BOption (b)

    30 g/mL

  3. COption (c)

    10 mL/g

  4. DOption (d)

    40 mL/g

View answer & explanation

Correct answer

Answer: (c)C.

10 mL/g

Why this answer is correct

Explanation

Sludge volume index (SVI)

  • It is the volume occupied in mL by one gm of solids in the mixed liquor after settling for 30 minutes.
  • It indicates the physical state of sludge produced in a biological aeration system.
  • It is used to decide the rate of recycling of sludge (Q) required to maintain the desired Mixed Liquor Suspended Solids (MLSS) and Food to Microorganism (F/M) ratio in the aeration tank to achieve the desired degree of purification. So by reducing the recycling ratio SVI can be controlled.

Calculation

The settled sludge volume Vob = 30 cm3/lit 

 = 30 mL/lit

The concentration of suspended solids in mixed liquor, Xob = 3 g/lit

\(\therefore {\rm{SVI}} = \frac{{{{\rm{V}}{{\rm{ob}}}}}}{{{{\rm{X}}{{\rm{ob}}}}}} = \frac{{30}}{3} = 10{\rm\space{mL}}/{\rm{gm}}\)

Question 50

What does the high COD to BOD ratio of an organic pollutant represent?

  1. AOption (a)

    Presence of toxic material in the pollutant

  2. BOption (b)

    Presence of free oxygen for aerobic decomposition

  3. COption (c)

    High biodegradability of the pollutant

  4. DOption (d)

    Low biodegradability of the pollutant

View answer & explanation

Correct answer

Answer: (d)D.

Low biodegradability of the pollutant

Why this answer is correct

Explanation:

COD (Chemical oxygen demand):

It is the amount of oxygen required for the decomposition of both biodegradable & non-biodegradable organic matter present in the system.

BOD (Biochemical oxygen demand):

  • It is the amount of oxygen required for the decomposition of biodegradable organic matter present in the system.
  • BOD during 5 days at 20°c is taken as standard BOD and is approximately 68% of the ultimate BOD.

​ThOD (Theoretical oxygen demand):

If the type of organic matter and its concentration present in the system is known then the amount of oxygen required for its decomposition can be computed theoritacly and is termed as ThOD.

TOC (Total organic carbon):

TOC is just another way to express the concentration of organic matter present in the system in terms of its carbon content.

BOD to COD ratio:

  • It signifies the quality of wastewater with respect to the type of organic matter present in it that is either biodegradable or non-biodegradable.
  • If the value of this ratio high that means the biodegradable organic matter is high and vice-versa.

Question 51

Which of the following treatment process are necessary for the removing suspended solids from water?

a) Coagulation

b) Sedimentation

c) Flocculation

d) Disinfection

Select the correct answer using the codes given below:

  1. AOption (a)

    a and b

  2. BOption (b)

    a, b and c

  3. COption (c)

    b and d

  4. DOption (d)

    a and d

View answer & explanation

Correct answer

Answer: (b)B.

a, b and c

Why this answer is correct

Explanation:

Sedimentation:

(i) The process of removal of suspended solids from the water is termed as sedimentation.

(ii) Sedimentation is a natural process by which solids with higher density than the fluid in which they are suspended, settles under the action of gravity.

(iii) Sedimentation tanks are designed to reduce the velocity of flow to reduce turbulence.

(iv) Efficiency of sedimentation is comparatively less if water consists of fine suspended particle, hence in such cases coagulation aided sedimentation is adopted.

(v) Coagulation aided sedimentation is performed in 3 stages:

  • Coagulation (Fast mixing)
  • Flocculation (slow mixing)
  • Sedimentation

Coagulation:

(i) It is the process in which certain chemical terms as coagulants are added in the water so as the neutralise negative protective charge over the particle to increase their opportunity to come in contact with each other, thus grow in size and get easily settled in following sedimentation process.

(ii) To neutralise the charge over the suspended impurities minimum energy (threshold energy) is required which is provided by induced fast mixing in this process

Flocculation:

(i) Flocculation is the process in which neutralise particle is brought in intimate contact with each other to promote their agglomeration resulting in increase size of flocs, which can get easily settled in the following sedimentation process.

(ii) To increase the opportunity of the neutralise particle to come in contact with each other slow mixing is induced during flocculation.

Question 52

If the coliform bacteria are present in a sample of water, then the coliform test to be conducted is

a. Presumptive coliform test

b. Confirmed coliform test

c. Completed coliform test

The correct answer is

  1. AOption (a)

    Only a

  2. BOption (b)

    Both a and b

  3. COption (c)

    Both a and c

  4. DOption (d)

    All a, b, and c

View answer & explanation

Correct answer

Answer: (d)D.

All a, b, and c

Why this answer is correct

Explanation:

coliform bacteria:

(i) Coliform bacteria are organisms that are present in the environment and in the feces of all warm-blooded animals and humans.

(ii) Coliform bacteria will not likely cause illness. However, their presence in drinking water indicates that disease-causing organisms (pathogens) could be in the water system. Most pathogens that can contaminate water supplies come from the feces of humans or animals.

(iii) Testing drinking water for all possible pathogens is complex, time-consuming, and expensive. It is relatively easy and inexpensive to test for coliform bacteria.

(iv) If coliform bacteria are found in a water sample, water system operators work to find the source of contamination and restore safe drinking water.

(v) There are three different groups of coliform bacteria; each has a different level of risk, Total coliform, fecal coliform, and E. coli

(vi) Total coliform, fecal coliform, and E. coli are all indicators of drinking water quality.

(vii) The total coliform group is a large collection of different kinds of bacteria. Fecal coliforms are types of total coliform that mostly exist in feces. E. coli is a sub-group of fecal coliform.

(Viii) When a water sample is sent to a lab, it is tested for total coliform. If total coliform is present then the Presumptive coliform test is confirmed, the sample will also be tested for fecal coliform and if fecal coliform is present then the Confirmed coliform test is complete and then again water sample is tested for E. coli, if E. coli is present then the Completed coliform test is done.

Question 53

The relative stability of a sewage sample, whose DO equals the total oxygen required to satisfy its BOD, is _______

  1. AOption (a)

    zero

  2. BOption (b)

    100 %

  3. COption (c)

    1 %

  4. DOption (d)

    ∞

View answer & explanation

Correct answer

Answer: (b)B.

100 %

Why this answer is correct

Explanation:

Relative stability:

The ratio of oxygen available in the wastewater (as dissolved oxygen) to the total oxygen required to satisfy its first state BOD is called relative stability.

Relative;stability;=;BOD;removedTotal;BOD×100Relative;stability; = ;\frac{{BOD;removed}}{{Total;BOD}} \times 100

Note:

As the DO level of the sewage is equal to the total oxygen required to decompose the organic matter present, total BOD will be removed.

∴ Relative stability = 100%

Question 54

Which of the following parameters are employed in the design of Trickling filter?

a. Hydraulic loading rate

b. Organic loading rate

c. Detention time

d. Weir loading rate

  1. AOption (a)

    a, b, c and d

  2. BOption (b)

    a and b only

  3. COption (c)

    b and c only

  4. DOption (d)

    c and d only

View answer & explanation

Correct answer

Answer: (b)B.

a and b only

Why this answer is correct

Explanation:

Trickling filter is a device that is used for the treatment of sewage. It is based on an aerobic attached growth system. Following factor affecting the rate of removal of organic matter in T.F.

(i) Temperature

(ii) Hydraulic loading rate

(iii) Organic loading rate

Following design parameters used in the trickling filter.

(i) **Hydraulic loading rate (m3/m2/day) (**Gives the area of the filter required)

(ii) Organic loading rate (kg/m3/day) ( Decide the volume of the filter)

(iii) Depth

Question 55

A concrete sewer of diameter 1.2 m is laid at a slope of 1 in 1000. The velocity of flow inside the sewer is 0.9 m/s when running full. What will be velocity of flow in the sewer when it is running half full?

  1. AOption (a)

    0.45 m/s

  2. BOption (b)

    1.8 m/s

  3. COption (c)

    1.35 m/s

  4. DOption (d)

    0.9 m/s

View answer & explanation

Correct answer

Answer: (d)D.

0.9 m/s

Why this answer is correct

Given:

d = 1.2 m

s=11000s = \frac{1}{{1000}}

Velocity when sewer runs full (Vfull) = 0.9 m/s

Vfull=1n;Rf23S12{V_{full}} = \frac{1}{n};R_f^{\frac{2}{3}}\frac{{{S^1}}}{2}

Vhalf=1nRh23;S12{V_{half}} = \frac{1}{n}R_h^{\frac{2}{3}};{S^{\frac{1}{2}}}

Rf=AfPf=(πD24)πD=D4{R_f} = \frac{{{A_f}}}{{{P_f}}} = \frac{{\left( {\frac{{\pi {D^2}}}{4}} \right)}}{{\pi D}} = \frac{D}{4}

Rh=AhPh=(πD28)(πD2)=D4{R_h} = \frac{{{A_h}}}{{{P_h}}} = \frac{{\left( {\frac{{\pi {D^2}}}{8}} \right)}}{{\left( {\frac{{\pi D}}{2}} \right)}} = \frac{D}{4}

VhalfVfull=(1n)(D4)23(S)12(1n)(D4)23(S)12=1\frac{{{V_{half}}}}{{{V_{full}}}} = \frac{{\left( {\frac{1}{n}} \right){{\left( {\frac{D}{4}} \right)}^{\frac{2}{3}}}{{\left( S \right)}^{\frac{1}{2}}}}}{{\left( {\frac{1}{n}} \right){{\left( {\frac{D}{4}} \right)}^{\frac{2}{3}}}{{\left( S \right)}^{\frac{1}{2}}}}} = 1

Vhalf = Vfull = 0.9 m/s

Question 56

Self-purification of running streams may be due to:

  1. AOption (a)

    dilution, sedimentation and oxidation

  2. BOption (b)

    sedimentation, oxidation and coagulation

  3. COption (c)

    dilution, sedimentation and coagulation

  4. DOption (d)

    dilution, oxidation and coagulation

View answer & explanation

Correct answer

Answer: (a)A.

dilution, sedimentation and oxidation

Why this answer is correct

Explanation:

Self-purification of running stream:

When the sewage effluent is disposed of in a river stream it undergoes the process of self-purification by the following natural mechanism;

Dilution & Dispersion:

In real terms, it is not the mechanism of self-purification it only reduces the potential hazard of the sewage effluent into the river stream.

Sedimentation:

As per the turbulence available in the river stream organic suspended particles get settled in it thereby helping the river water to get self purified.

Sunlight:

In the presence of sunlight, a photosynthesis reaction takes place during which O2 is released which is utilized by the micro-organism for the decomposition of organic matter thereby helping the river water to get self purified.

Oxidation & Reduction:

Decomposition of the organic matter by the action of micro-organism over the surface of the river stream and by the anaerobic micro-organism on the bed of the river collectively helps the river to get self purified.

Question 57

If the height of a tower is 50 m, flying height of the aircraft above the base is 5000 m and the image of the top of the tower is 20 cm, from the principal point, what will be the height displacement?

  1. AOption (a)

    2 cm

  2. BOption (b)

    1 cm

  3. COption (c)

    0.2 cm

  4. DOption (d)

    0.2 m

View answer & explanation

Correct answer

Answer: (c)C.

0.2 cm

Why this answer is correct

Concept:

Relief Displacement:

(i) Relief is the elevation of object above or below the datum. Relief displacement is the lateral

displacement (also called shift) in the position of image on the photograph of a ground object.

(ii) Relief displacement is given by;

Relief;displacement;(d)=rhHRelief;displacement;\left( d \right) = \frac{{rh}}{H}

Where, h = Height of the object above datum

H = Flying height above datum

r = Radial distance of the image of the object top 

Calculation:

Given,

h = 50 m, H = 5000 m, r = 20 cm

Now,

Relief;displacement;(d)=20×505000=0.2;cmRelief;displacement;\left( d \right) = \frac{{20 \times 50}}{{5000}} = 0.2;cm

Question 58

The perpendicular offset from a tangent to the junction of transition curve and circular curve is equal to:

(Where L = Length of transition curve, R = Radius of the circular curve)

  1. AOption (a)

    L/6R

  2. BOption (b)

    L/24R

  3. COption (c)

    L2/(6R)L^2/(6 R)

  4. DOption (d)

    L2/(24R)L^2/(24 R)

View answer & explanation

Correct answer

Answer: (c)C.

L2/(6R)L^2/(6 R)

Why this answer is correct

Concept:

The distance through which the curve is shifted is known as shift (S) of the curve and is equal to

 S=L224R{\bf{S}} = \frac{{{{\bf{L}}^2}}}{{24{\bf{R}}}}

where,

L is the length of each transition curve and R is the radius of the desired circular curve

The offset for the transition curve is given by: -

offset;(y)=ℓ36RL{\bf{offset}};\left( {\bf{y}} \right) = \frac{{{\ell ^3}}}{{6{\bf{RL}}}}

Where,

ℓ = measured along the curve (m),

R = radius of the curve (m), and

L = length of the curve (m)

∴ For offset at the junction point, ℓ = L

y=l36RL=L36RL=L26R{\bf{y}} = \frac{{{{\bf{l}}^3}}}{{6{\bf{RL}}}} = \frac{{{{\bf{L}}^3}}}{{6{\bf{RL}}}} = \frac{{{{\bf{L}}^2}}}{{6{\bf{R}}}}         

Important Points

 The relation between Shift of curve S and offset of transition curve is:

 4 × S = Offset

Question 59

In a survey, A and B are two points. Already located with respect to A and B, point C is located by taking two readings, and then line CD is measured. The D is a point on AB. The line CD is known as

  1. AOption (a)

    Base line

  2. BOption (b)

    Check line

  3. COption (c)

    Tie line

  4. DOption (d)

    Additional line

View answer & explanation

Correct answer

Answer: (c)C.

Tie line

Why this answer is correct

Explanation:

(i) If the distance of the point or detail from the chain line is very large, then long offsets need to be taken.

(ii) Tie lines are the lines that are run to locate details in order to avoid long offsets.

So line CD represented in the figure is a tie line.

Important point:

Base line: It is the long survey line which is run through the middle of the area to be surveyed. The frame work of triangles is built on the base line.

Here AB is the base line

Check line:

(i) These lines are run to check the accuracy of the traverse consisting of a frame work of triangles

(ii) Check lines are measured in the field during the survey process of the land.

(iii) It is also known as Proof lines.

Question 60

A tunnel should NOT be constructed along:

  1. AOption (a)

    Strike direction

  2. BOption (b)

    Dip direction

  3. COption (c)

    Oblique to the bed altitude

  4. DOption (d)

    Both along dip and strike direction

View answer & explanation

Correct answer

Answer: (a)A.

Strike direction

Why this answer is correct

Explanation:

(i) In strike direction case, that is, when the tunnel is driven parallel to strike of the bed. The pressure distribution to the exposed layers is unsymmetrical along the periphery of the tunnel opening.

(ii) In case of parallel to the dip direction, the layers offer a uniformly distributed load on the excavation, even relatively weaker rocks might act as self-supporting in such cases.

Note:

Two expressions commonly used to describe the rock structure are ‘strike’ and ‘dip’. Strike is the horizontal direction of the structure on the rock surface.

Dip is the angle of the structure relative to the horizontal rock surface.

Question 61

Refraction error is least in case of

  1. AOption (a)

    Stadia tacheometry

  2. BOption (b)

    Tangential tacheometry

  3. COption (c)

    Subtense bar tacheometry

  4. DOption (d)

    Omnimeters

View answer & explanation

Correct answer

Answer: (c)C.

Subtense bar tacheometry

Why this answer is correct

Explanation:

Tachometer:

(i) Tacheometer is nothing but a transit theodolite fitted with a stadia diaphragm.

(ii) The stadia diaphragm generally consists of two hairs, one above and one below and equidistant from a central horizontal hair.

Systems of Tacheometric measurements:

(a) Stadia system

(b) Tangential system

(c) Subtense bar system

(a) Stadia system:

(i) In the stadia system of tacheometry of, the tacheometer is set up station A and staff at station B.

(ii) The staff intercept between the upper and lower stadia is measured along with vertical angle θ made with horizontal.

(iii) The horizontal distance D between the instrument station A and staff station B and the difference of elevation between stations A and B are determined from the staff intercept (s) and the vertical angle.

(iv) Refraction correction may occur during measurement.

(b) Tangential system:

(i) Here in this system of tacheometry, the hairs are not at all required.

(ii) This method can even be used when telescope is not provided with a diaphragm.

(iii) The staff had two targets at a fixed distance (s) apart.

(iv) The vertical angles θ1 and θ2 are measured to the two targets.

(v) Now these vertical angles and the fixed distance on staff are used to determine the horizontal distance and difference of elevation.

(C) Subtense bar system:

(i) Here in this system of tacheometry, a bar of fixed length is used which is known as subtense bar as shown in fig.

(ii) The subtense bar has two targets at the ends at a fixed distance (s) apart.

(iii) The horizontal angle subtended between the instrument station A and the two targets on the subtense bar is measured.

(iv) In subtense bar system less chance of refraction error because the line of sight does not change the path

Question 62

If two triangulation signals of 6.75 m height each are to be just visible over ground mutually, what is the maximum distance between their locations on the ground surface?

  1. AOption (a)

    10 km

  2. BOption (b)

    20 km

  3. COption (c)

    30 km

  4. DOption (d)

    50 km

View answer & explanation

Correct answer

Answer: (b)B.

20 km

Why this answer is correct

Concept:

Distance of visible Horizon:

Let there is a point C at an elevation h from the mean sea level. A is the point on the horizon as observed from C. The tangent from C meets the mean sea level at A. The distance AC is the distance of visible horizon.

h = 0.0673d2

d = 3.855 √h

Where,

d = Distance AC (in km)

h = height of the object (in m)

Calculation:

Given,

 h1 = h2 = 6.75 m

So total distance = d1 + d2

d1 + d2 = 3.855 √h1 + 3.855 √h2

d1 + d2 = 3.855 √6.75 + 3.855 √6.75 = 20.03 km

d1 + d2 ≈ 20 km

Question 63

The system that uses the Sun as a source of electromagnetic energy and records the naturally radiated and reflected energy from the object is called

  1. AOption (a)

    Geographical Information System

  2. BOption (b)

    Global Positioning System

  3. COption (c)

    Passive Remote Sensing

  4. DOption (d)

    Active Remote Sensing

View answer & explanation

Correct answer

Answer: (c)C.

Passive Remote Sensing

Why this answer is correct

The correct answer is 'Passive Remote Sensing'

Key Points

  • passive remote sensing:
  • Passive remote sensing is a system that relies on the Sun as the natural source of electromagnetic energy.
  • It records the energy that is naturally reflected or emitted by objects on the Earth’s surface.
  • Sensors in passive remote sensing do not generate their own energy; instead, they depend on available solar radiation or thermal emission.
  • This system is widely used for observing landforms, vegetation, water bodies, and atmospheric conditions.

Additional Information

  • geographical information system:
  • GIS is a computer-based system used for storing, analyzing, and displaying spatial data.
  • It does not involve sensing or recording electromagnetic energy from objects.
  • global positioning system:
  • GPS is a satellite-based navigation system used to determine precise locations on Earth.
  • It does not record reflected or emitted electromagnetic radiation from objects.
  • active remote sensing:
  • Active remote sensing systems emit their own electromagnetic energy toward the Earth’s surface.
  • They record the energy reflected back, rather than relying on natural solar radiation.

Important Points

  • Passive remote sensing depends on natural energy sources, mainly sunlight.
  • It records both reflected solar radiation and naturally emitted thermal energy.
  • Most optical satellite images are obtained using passive remote sensing techniques.

Question 64

The ratio of curvature correction to that of refraction is:

  1. AOption (a)

    3

  2. BOption (b)

    12

  3. COption (c)

    14

  4. DOption (d)

    7

View answer & explanation

Correct answer

Answer: (d)D.

7

Why this answer is correct

Explanation

We know,

Curvature correction is given by:

Cc=d22R{C_c} = \frac{{{d^2}}}{{2R}}

Where,

d = distance between points under consideration

R = Radius of earth = 6370 km

Refraction correction:

CR=17×d22R=d214R{C_R} = \frac{1}{7} \times \frac{{{d^2}}}{{2R}} = \frac{{{d^2}}}{{14R}}

So,

The ratio of curvature correction to refraction correction is 1/(1/7) = 7

∴ Ratio is 7

Question 65

 In a vertical curve, an upgrade of 2.0% is followed by a downgrade of 2.0%. The rate of change of grade is 0.05% per 20 m chain. The length of the vertical curve will be:

  1. AOption (a)

    800 m

  2. BOption (b)

    1000 m

  3. COption (c)

    1200 m

  4. DOption (d)

    1600 m

View answer & explanation

Correct answer

Answer: (d)D.

1600 m

Why this answer is correct

Explanation

Given,

 Upgrade of 2.0 % followed by the downgrade of 2 % 

 N1 = 2 % , N2 = - 2%

  Rate of change of grade is 0.05 % per 20 m chain.

 Total change in grade (N) = N1 – N2

 N= 2 % - (- 2%) = 2% + 2%

 N = 4 %

Total;Length=40.05×20=1600;m{\rm{Total;Length}} = \frac{4}{{0.05}} \times 20 =1600;m

Question 66

Repetition of beds on a geological map may be due to

  1. AOption (a)

    Unconformity

  2. BOption (b)

    Disconformity

  3. COption (c)

    Faulting

  4. DOption (d)

    Folding

View answer & explanation

Correct answer

Answer: (d)D.

Folding

Why this answer is correct

Explanation:

Structural geology:

Structural geology is the study of factors such as origin, occurrence, classification, type, and effects of various secondary structures like folds, faults, joints, rock cleavage and are different from those primary structures such as bedding and vesicular structure, which develop in rocks at the time of their formation.

Folds:

(i) Folds are one of the most common geological structures found in rocks. When a set of horizontal layers are subjected to compressive forces, they bend either upward or downward. The bend noticed in rocks are called folds.

(ii) In terms of their nature too, folds may occur as single local bends or may occur repeatedly and intricately folded to the tectonic history of the region.

joints and Faults:

(i) Structurally, faults may be described as fractures along which relative displacement of adjacent blocks has taken place.

(ii) If such relative displacement does not take place on either side of the fracture plane, it is called a joint. Thus both joints and faults are fractures in rocks but with differences in the kind of displacement. Joints may be described as a set of aligned parallel cracks or openings in geological formations.

Question 67

The velocity distribution in turbulent flow is a function of the distance ‘y’ measured from the boundary surface and the friction velocity μ* and follows :

  1. AOption (a)

    parabolic law

  2. BOption (b)

    hyperbolic law

  3. COption (c)

    logarithmic law

  4. DOption (d)

    linear law

View answer & explanation

Correct answer

Answer: (c)C.

logarithmic law

Why this answer is correct

Explanation:

Velocity Distribution for Turbulent Flow in pipes.

Prandtl’s universal velocity distribution equation.

v=vmax+2.5V∗log⁡e(yR)v = {v_{max}} + 2.5{V^*}{\log _e}\left( {\frac{y}{R}} \right)

Where,  V∗=τ0ρ=Shear;or;friction;velocity.{V^*} = \sqrt {\frac{{{\tau _0}}}{\rho }} = Shear;or;friction;velocity.

y = distance from the pipe wall

ρ = Density of fluid.

On observing the above equation we can say that velocity distribution in the turbulent boundary layer follows logarithmic law.

Important Points

The above equation is valid for both smooth and rough pipes.

Question 68

While conducting flow measurement using a rectangular notch, an error of 2% in head over the notch and error of 3% in the length was observed. The percentage error in the computed discharge would be

  1. AOption (a)

    +6%

  2. BOption (b)

    -1%

  3. COption (c)

    -2.5%

  4. DOption (d)

    Zero

View answer & explanation

Correct answer

Answer: (a)A.

+6%

Why this answer is correct

Concept:

Flow over a Rectangular notch:

Discharge measured through rectangular notch:

 Q=23Cd2gLH3/2Q = \frac{2}{3}{C_d}\sqrt {2g} L{H^{3/2}}

Where, Cd = Coefficient of discharge

L = Length of crest or sill

H = Still water head

Effect on computed discharge over a weir or notch due to error in the measurement of head and length:

 Q=23Cd2gLH3/2Q = \frac{2}{3}{C_d}\sqrt {2g} L{H^{3/2}}

Or, Q=KLH3/2Q = KL{H^{3/2}}

Where, K=23Cd2gK = \frac{2}{3}{C_d}\sqrt {2g}

Differentiating the above equation

dQ = KH3/2dL + KL × (3/2) H1/2 dH

 dQQ=dLL+32dHH;\frac{{dQ}}{Q} = \frac{{dL}}{L} + \frac{3}{2}\frac{{dH}}{H};

Calculation:

Give,

dHH=2%\frac{{dH}}{H} = 2\%

dLL=3%\frac{{dL}}{L} = 3\%

So, the Percentage error in discharge,

dQQ=dLL+32dHH\frac{{dQ}}{Q} = \frac{{dL}}{L} + \frac{3}{2}\frac{{dH}}{H}

dQQ=3%+32×;2%=6%\frac{{dQ}}{Q} = 3\% + \frac{3}{2} \times ;2\% = 6\%

Question 69

A pipe is said to be equivalent to another, if both 

  1. AOption (a)

    Length and discharge are the same

  2. BOption (b)

    Velocity and diameter are the same

  3. COption (c)

    Discharge and the frictional head loss are the same

  4. DOption (d)

    length and diameter are the same

View answer & explanation

Correct answer

Answer: (c)C.

Discharge and the frictional head loss are the same

Why this answer is correct

Explanation:

  • The equivalent length method (L/D ratio) allows describing the pressure drop through the pipe due to friction loss corresponding to flow rate i.e. if in the two pipe of a system having same flow rate and same friction loss then this system of the pipe is said to be equivalent.
  • An equivalent pipe is defined as the pipe of uniform diameter having loss of head and discharge equal to the loss of head and discharge of a compound pipe consisting of several pipes of different lengths and diameters.
  • There are two combinations of equivalent pipe system:
  1. Pipes connected in series
  2. Pipes connected in parallel

For pipes connection in series:

  • The discharge through all the pipes is the same and equivalent head loss is the sum of head loss in all the individual pipes.
  • Qeq = Q1 = Q2 = … and heq = h1 + h2 + …..
  • leqdeq5=l1d15+l2d25+…\frac{{{l_{eq}}}}{{d_{eq}^5}} = \frac{{{l_1}}}{{d_1^5}} + \frac{{{l_2}}}{{d_2^5}} + \ldots
  • For pipes of the same diameter as all the pipes equivalent length of the pipe is given by the sum of the length of all the pipes.

For pipes connected in parallel:

  • The head loss through all the pipes is the same and equivalent discharge is the sum of discharge in all the individual pipes.
  • heq = h1 = h2 = …. and Qeq = Q1 + Q2 + …
  • leqdeq5=l1d15=l2d25;and;(deq5leq)12=(d15l1)12+(d25l2)12+…\frac{{{l_{eq}}}}{{d_{eq}^5}} = \frac{{{l_1}}}{{d_1^5}} = \frac{{{l_2}}}{{d_2^5}}{\rm{;and;}}{\left( {\frac{{d_{eq}^5}}{{{l_{eq}}}}} \right)^{\frac{1}{2}}} = {\left( {\frac{{d_1^5}}{{{l_1}}}} \right)^{\frac{1}{2}}} + {\left( {\frac{{d_2^5}}{{{l_2}}}} \right)^{\frac{1}{2}}} + \ldots
  • For pipes of equal length and diameter deq = n2/5d

Question 70

A channel designed by Lacey’s theory has a mean velocity of 1 m/sec. the silt factor is unity. The hydraulic mean radius will be 

  1. AOption (a)

    2.5 m

  2. BOption (b)

    2.0 m

  3. COption (c)

    1.5 m

  4. DOption (d)

    0.5 m

View answer & explanation

Correct answer

Answer: (a)A.

2.5 m

Why this answer is correct

Concept:

Design steps by Lacey’s theory-

1)  Calculate velocity of flow from given value of discharge, V = (QF2140)16{\left( {\frac{{Q{F^2}}}{{140}}} \right)^{\frac{1}{6}}}

Where,

F = silt factor = 1.76√d50 and d50 = average size of soil particles in mm.

2) Calculation of area of cross-section of canal, A = Q/V

3) Calculation of perimeter, P = 4.75√Q

4) Calculate hydraulic radius, R = 52V2F\frac{5}{2}\frac{{{{\rm{V}}^2}}}{{\rm{F}}}

5) Calculate bed slope, S = F533340Q16\frac{{{{\rm{F}}^{\frac{5}{3}}}}}{{3340{{\rm{Q}}^{\frac{1}{6}}}}}

Calculation:

Hydraulic mean radius, R = 52×V2F=52×121\frac{5}{2} \times \frac{{{{\rm{V}}^2}}}{{\rm{F}}} = \frac{5}{2} \times \frac{{{1^2}}}{1} = 2.5 m

Important point:

All the units except d50 (which is in mm) are in SI units.

Question 71

The pressure drop per unit length of the pipe(ΔP/L) in the laminar flow is dependent on the velocity, viscosity and diameter. It is equal to:

  1. AOption (a)

    d232μV\frac{d^2}{32\mu V}

  2. BOption (b)

    32 μVLγd2\frac{32\ \mu VL}{\gamma d^2}

  3. COption (c)

    32 μVd2\frac{32\ \mu V}{d^2}

  4. DOption (d)

    8 μVd2\frac{8\ \mu V}{d^2}

View answer & explanation

Correct answer

Answer: (c)C.

32 μVd2\frac{32\ \mu V}{d^2}

Why this answer is correct

Concept:

The pressure drop head in a laminar flow through the circular pipe is given by:

P1−P2ρg=32;μVLρgd2\frac{{{P_1} - {P_2}}}{{ρ g}} = \frac{{32;μ VL}}{{ρ g{d^2}}}

ΔP=32;μVLd2Δ P = \frac{{32;μ VL}}{{{d^2}}}

ΔPL=32;μVd2\frac{Δ P}{L} = \frac{{32;μ V}}{{{d^2}}}

Where, ΔP = Pressure drop, μ = viscosity of the fluid, V = Mean velocity of flow, L = Length of pipe, D = diameter of the pipe, ρ = Density of the fluid

Question 72

The ratio of pressures between the two points A and B located respectively at depth 0.25 m and 0.75 m below a constant level of water in a tank is

  1. AOption (a)

    1 : 2

  2. BOption (b)

    1 : 3

  3. COption (c)

     1 : 4

  4. DOption (d)

    1 : 5

View answer & explanation

Correct answer

Answer: (b)B.

1 : 3

Why this answer is correct

Explanation

From the hydrostatic law:

Pressure at any point X any height h1, Px = ρgh1

Pressure at any point Y any height h2, Py = ρgh2

Given, 

 Depth of point A = 0.25 m

∴ Pressure at point A = ρ × g × 0.25

 Depth of point B = 0.75 m 

∴ Pressure at point A = ρ × g × 0.75

PAPB=ρ×g×hAρ×g×hB=hAhB=0.250.75=13\frac{{{P_A}}}{{{P_B}}} = \frac{{{\rho \times g\times h_A}}}{{{\rho \times g\times h_B}}} =\frac{{h_A}}{h_B}= \frac{{0.25}}{0.75} = \frac{1}{{3}}

Question 73

A circular plate 1 m in diameter is submerged vertically in water such that its upper edge is 8 m below the free surface of water. The total hydrostatic pressure force on one side of plate is:

  1. AOption (a)

    6.7 kN

  2. BOption (b)

    65.4 kN

  3. COption (c)

    45.0 kN

  4. DOption (d)

    77.0kN

View answer & explanation

Correct answer

Answer: (b)B.

65.4 kN

Why this answer is correct

Calculation:

D = 1m;

y = 8 m;

F = ρ.g.h−.A=ρ.g.(y+D2).π4D2\rho .g.\mathop h\limits^ - .A = \rho .g.\left( {y + {D \over 2}} \right).{\pi \over 4}{D^2}

=1000×9.81(8+12)×π412=65.4kN = 1000 \times 9.81\left( {8 + {1 \over 2}} \right) \times {\pi \over 4}{1^2} = 65.4kN

Question 74

When there is an increase in the atmospheric pressure, the water level in a well penetrating a confined aquifer

  1. AOption (a)

    decreases

  2. BOption (b)

    increases

  3. COption (c)

    does not undergo any change

  4. DOption (d)

    decrease or increase depending on the elevation of the ground

View answer & explanation

Correct answer

Answer: (a)A.

decreases

Why this answer is correct

Explanation:

Confiner aquifer:

(i) It is confined between two impervious layers (Ex. Aquiclude or Aquifuge). Overlying layer act as a layer confining the underlying aquifer, so it is called confined aquifer.

(ii) The water in the confined aquifer is not direct contactt with the atmosphere, so the water within a confined aquifer occurs under pressure (confined pressure), which is greater than atmospheric pressure.

(iii) When it is pierced by a well, the water rises in the well due to the release of pressure, the level up to which water will rise in the well is known as potentiometric level (piezometric level)

Question 75

A turbine in which the total energy of water available is converted to kinetic energy is called:

  1. AOption (a)

    Axial flow turbine

  2. BOption (b)

    Reaction turbine

  3. COption (c)

     Impulse turbine

  4. DOption (d)

    Mixed flow turbine

View answer & explanation

Correct answer

Answer: (c)C.

 Impulse turbine

Why this answer is correct

Explanation:

Impulse turbine: 

  • If the energy available at the inlet of the turbine is only kinetic energy, the turbine so known as impulse turbine.
  • The available energy at the inlet is only kinetic energy if the inlet pressure and outlet pressure is the same equal to atmospheric pressure.
  • Example: Pelton Turbine

Reaction Turbine: 

  • At the inlet of the turbine, the water possesses kinetic energy as well as pressure energy
  • Example: Francis Turbine, Kaplan Turbine

Important Points

Impulse:

Impulse is the sudden change of momentum of an object when the object is acted upon by a force for an interval of time.

Question 76

The discharge per unit drawdown of a well, is called 

  1. AOption (a)

    specific storage

  2. BOption (b)

    specific yield

  3. COption (c)

    specific capacity

  4. DOption (d)

    None of the above

View answer & explanation

Correct answer

Answer: (c)C.

specific capacity

Why this answer is correct

Explanation:

Specific Capacity:

(i) Specific Capacity of a well is defined as the rate of flow through the well per unit drawdown.

(ii) The specific capacity is not the same for all the unit drawdown, but it is computed only for the initial first-meter fall of the height of water in the well.

QSpecific;Capacity=Discharge;through;the;well;(Q)Unit;Drawdown;(ST){Q_{Specific;Capacity}} = \frac{{Discharge;through;the;well;\left( Q \right)}}{{Unit;Drawdown;\left( {{S_T}} \right)}}

Specific storage: 

It is the amount of water that a portion of an aquifer releases from storage, per unit mass or volume of the aquifer, per unit change in hydraulic head, while remaining fully saturated.

Specific yield: 

It is defined as the volume of water released from storage by an unconfined aquifer per unit surface area of the aquifer per unit decline of the water table.

Question 77

A stream that provides water to the water table is termed as

  1. AOption (a)

    Affluent

  2. BOption (b)

    Influent

  3. COption (c)

    Ephemeral

  4. DOption (d)

    Effluent

View answer & explanation

Correct answer

Answer: (b)B.

Influent

Why this answer is correct

Explanation:

Effluent stream: A stream into which water is discharged from the ground-water reservoir, sometimes called a gaining stream

Influent Stream: A losing stream, disappearing stream, influent stream or sinking river is a stream or river that loses water as it flows downstream. The water infiltrates into the ground recharging the local groundwater because the water table is below the bottom of the stream channel.

So it is clear that A stream that provides water to the water table is known as an influent stream.

Question 78

The observed annual runoff from a basin of area 500 km2 is 150 Mm3 and the corresponding annual rainfall over the basin during the same year is 750 mm. What is the runoff coefficient?

  1. AOption (a)

    0.2

  2. BOption (b)

    0.67

  3. COption (c)

    0.4

  4. DOption (d)

    0.5

View answer & explanation

Correct answer

Answer: (c)C.

0.4

Why this answer is correct

Explanation

∵ We know that,

Runoff coefficient = Runoff/Rainfall

Given,

Runoff = 150 Mm3

Rainfall depth = 750 mm

Area = 500 km2

Rainfall depth in terms of volume = 0.75 × 500 = 375 Mm3 (1 million-m = 106 m)

Runoff coefficient = 150/375

= 0.4

Question 79

The theissen weights of 4 rain gauges A, B, C and D covering a river basin are 0.15, 0.25, 0.30 and 0.30 respectively. If the average depth of rainfall for the basin is 5 cm and rainfall recorded at B, C and D are 5 cm, 4 cm and 5 cm respectively, what is the rainfall at A?

  1. AOption (a)

    5 cm

  2. BOption (b)

    6 cm

  3. COption (c)

    7 cm

  4. DOption (d)

    8 cm 

View answer & explanation

Correct answer

Answer: (c)C.

7 cm

Why this answer is correct

Concept:

Thiessen polygon method:

In this method, the rainfall recorded at each station is given a weightage on the basis of area closest to the station. The average precipitation over the catchment area is given as,

Pavg=P1A1+P2A2+P3A3+…PnAnA1+A2+A3+…An=P1A1+P2A2+P3A3+…PnAnA{P_{avg}} = \frac{{{P_1}{A_1} + {P_2}{A_2} + {P_3}{A_3} + \ldots {P_n}{A_n}}}{{{A_1} + {A_2} + {A_3} + \ldots {A_n}}} = \frac{{{P_1}{A_1} + {P_2}{A_2} + {P_3}{A_3} + \ldots {P_n}{A_n}}}{A}

Where, \mathop \sum \limits_{i = 1}^n \frac{{{A_i}}}{A} is called the weightage factor

Calculation:

Given,

Pavg = 5 cm

PB = 5 cm, PC = 4 cm, PD = 5 cm

PA =?

Weightage factor for station A, B, C and D is given, 0.15, 0.25, 0.30 and 0.30.

∵ We know, The average rainfall

Pavg=PAAA+PBAB+PCAC+PDADAA+AB+AC+AD=PAAA+PBAB+PCAC+PDADA{P_{avg}} = \frac{{{P_A}{A_A} + {P_B}{A_B} + {P_C}{A_C} + {P_D}{A_D}}}{{{A_A} + {A_B} + {A_C} + {A_D}}} = \frac{{{P_A}{A_A} + {P_B}{A_B} + {P_C}{A_C} + {P_D}{A_D}}}{A}

5 = PA × 0.15 + 5 × 0.25 + 4 × 0.30 + 5 × 0.30

5 = PA × 0.15 + 3.95

PA = 7 cm

Question 80

Water is to be lifted by a net head of 240 m. Identical pumps each with a specific speed of 30 and a rotational speed of 1450 rpm with design discharge 0.2 m3/s are available. The number of pumps required will be:

  1. AOption (a)

    2

  2. BOption (b)

    3

  3. COption (c)

    4

  4. DOption (d)

    5

View answer & explanation

Correct answer

Answer: (c)C.

4

Why this answer is correct

Concept:

Specific speed is given by

NS=Specific;speed(Rpm)=N;QHm34;{{\rm{N}}_S} = {\rm{Specific;speed}}\left( {{\rm{Rpm}}} \right) = \frac{{N;\sqrt Q }}{{H_m^{\frac{3}{4}}}};

Where,

N = design speed(rpm), Q = rated capacity(lit/sec),

Hm = manometric head, H = total head

For multistage pump:

No.;of;the;pump;in;series=Total;HeadHead;of;EacH;pump{\rm{No}}.{\rm{;of;the;pump;in;series}} = \frac{{Total;Head}}{{Head;of;EacH;pump}}

Calculation:

Given:

 NS = 30 rpm, N = 1450 rpm

 Q = 0.2 m3/s 

NS=N;QHm34,;30=1450×0.2Hm34{{\rm{N}}_S} = \frac{{N;\sqrt Q }}{{H_m^{\frac{3}{4}}}},;30= \frac{{1450 \times \sqrt {0.2} }}{{H_m^{\frac{3}{4}}}}

Hm34=21.61H_m^{\frac{3}{4}} = 21.61

 Hm = 60.21 ≈ 60 m

So, one pump can lift up to 60 m head.

Given,  For a net head of 240 m how many pumps are required,

∴ Number of pumps required = 240/60 = 4

∴ 4 number of pumps are required. 

Mistake point:

Some might get confused between these two formulae

One is for pump and other for turbine

NS(Pump)=N;QHm34,;NS(Turbine)=N;PHm54{{\rm{N}}_S}\left( {{\rm{Pump}}} \right) = \frac{{N;\sqrt Q }}{{H_m^{\frac{3}{4}}}},;{{\rm{N}}_S}\left( {{\rm{Turbine}}} \right) = \frac{{N;\sqrt P }}{{H_m^{\frac{5}{4}}}}

Question 81

For one-dimensional flow without recharge in an unconfined aquifer between two water bodies, the steady water table profile is

  1. AOption (a)

    a straight line

  2. BOption (b)

    a parabola

  3. COption (c)

    an ellipse

  4. DOption (d)

    an arc of a circle

View answer & explanation

Correct answer

Answer: (b)B.

a parabola

Why this answer is correct

Explanation:

Unconfined Flow: In unconfined flow, there is considerable difficulty in analytical solution by using Equation of Laplace for steady flow due to the following reason

(i) The line representing the water table is a streamline.

(ii) Free water surface of water table, known as phreatic surface, has the boundary conditions of constant pressure.

Unconfined flow with Recharge: In the unconfined aquifer case, the water table is represented by an ellipse equation.

δ2h2δx2=−2Rk\frac{{{\delta ^2}{h^2}}}{{\delta {x^2}}} = - \frac{{2R}}{k}

After integrating, applied boundary condition

Discharge, qx = R(x−L2)+K2L(ho;2−;h12)R\left( {x - \frac{L}{2}} \right) + \frac{K}{{2L}}\left( {h_{o;}^2 - ;h_1^2} \right)

Unconfined Flow without recharge: As there is no recharge, the water table is represented by a parabolic equation.

qx = K2L(ho;2−;h12)\frac{K}{{2L}}\left( {h_{o;}^2 - ;h_1^2} \right)

Question 82

As per the recommendation of Bureau of Indian Standard, The shape of the lined canal is

  1. AOption (a)

    Circular

  2. BOption (b)

    Trapezoidal

  3. COption (c)

    Parabolic

  4. DOption (d)

    Elliptical

View answer & explanation

Correct answer

Answer: (b)B.

Trapezoidal

Why this answer is correct

Explanation:

Canal Lining:

  • Canal Lining is an impermeable layer provided for the bed and sides of the canal to improve the life and discharge capacity of the canal.
  • 60 to 80% of water lost through seepage in an unlined canal can be saved by constructing canal lining.
  • The loss is more in the unlined canal as compared to the lined canal.
  • As per the recommendation of the Bureau of Indian Standard, The shape of the lined canal is Trapezoidal.

Advantage of the lining of the canal:

  • Prevents seepage loss and hence more area can be employed for irrigation.
  • Helps in the prevention of water logging.
  • Increased velocity in a canal prevents silting of the canal.

Disadvantage of lining canal:

  • It requires a heavy initial investment.
  • It is difficult to repair initial investment.

Question 83

Geological strata between ground surface and water table is also termed as

  1. AOption (a)

    Piezometric zone

  2. BOption (b)

    Phreatic zone

  3. COption (c)

    Vadose zone

  4. DOption (d)

    Saturated zone

View answer & explanation

Correct answer

Answer: (c)C.

Vadose zone

Why this answer is correct

Explanation:

(i) The vadose zone is the undersaturated portion of the subsurface that lies above the groundwater table. The soil and rock in the vadose zone are not fully saturated with water; that is, the pores within them contain air as well as water.

Important point:

Phreatic zone or Saturated Zone:

The phreatic zone or zone of saturation, is the part of an aquifer, below the water table, in which relatively all pores and fractures are saturated with water. Above the water table is the vadose zone. The phreatic zone size, color, and depth may fluctuate with changes of season, and during wet and dry periods.

Question 84

The standard BOD5 at 20°C, when compared to BODU is

  1. AOption (a)

    50%

  2. BOption (b)

    68%

  3. COption (c)

    75%

  4. DOption (d)

    100%

View answer & explanation

Correct answer

Answer: (b)B.

68%

Why this answer is correct

Explanation:

BOD5 at 20° is given by,

(BOD)5 = BODu × [1 – 10-KDt]      …….(i)

Where,

 BODu = Ultimate BOD

t = Time in days

KD = Deoxygenation rate constant (The value of KD determines the speed of the BOD reaction, without influencing the ultimate BOD)

KD is found to vary with the temperature of sewage and this relationship is approximately given by the equation,

KD(T°) = KD(20°) × [1.047]T-20°

Generally,

KD value at 20° C is 0.1 per day

From (i)

BOD5 = BODu × [1 – 10-0.1 × 5]

BOD5 = 0.6837 BODu

So, BOD5 is approx 68% of Ultimate BOD.

Question 85

Sludge bulking can be controlled by

  1. AOption (a)

    Chlorination

  2. BOption (b)

    Coagulation

  3. COption (c)

    Aeration

  4. DOption (d)

    Denitrification

View answer & explanation

Correct answer

Answer: (a)A.

Chlorination

Why this answer is correct

Explanation:

Sludge bulking:

(i) A Sludge that exhibits poor settling characteristics is called a bulking sludge. Filamentous micro-organisms (e.g. fungi) have been found to be responsible for a bulked sludge. Filamentous micro-organisms are observed due to low nutrient content, high sludge age, and low F/M ratio.

(ii) The most successful methods to control these organisms, as per latest research, are:

(a) Reduction of the sludge age to less than 6 days

(b) Chlorination of return activated sludge

(c) Addition of nutrient if it is less (BOD5 : N2 : P ratio recommends = 100 : 5 : 1)

Question 86

Uniformity coefficient of filter sand is given by

  1. AOption (a)

    D60D5\frac{{{{\rm{D}}_{60}}}}{{{{\rm{D}}_5}}}

  2. BOption (b)

    D50D5\frac{{{{\rm{D}}_{50}}}}{{{{\rm{D}}_5}}}

  3. COption (c)

    \(\frac{{{{\rm{D}}{50}}}}{{{{\rm{D}}{10}}}}\)

  4. DOption (d)

    \(\frac{{{{\rm{D}}{60}}}}{{{{\rm{D}}{10}}}}\)

View answer & explanation

Correct answer

Answer: (d)D.

\(\frac{{{{\rm{D}}{60}}}}{{{{\rm{D}}{10}}}}\)

Why this answer is correct

Explanation:

Grain size distribution curve:

(i) A graph is plotted between % finer and sieve size in the semi-log paper. Sieve size (particle dia) is taken on log scale on x-axis and % finer on the arithmetic scale on y-axis.

(ii) From the grain distribution curve is computed corresponding to 60% finer, 30% finer and 10% finer are computed. They are represented as D60, D30, and D10 respectively.

(iii) D10 is that size below which 10% particles are finer than this size by weight D10 is called effective size.

(iv) Using D60, D30, and D10, Following shape parameters are defined for the classification of coarse soils.

(a) Coefficient of uniformity, Cu = D60D10\frac{{{D_{60}}}}{{{D_{10}}}}

(b) Coefficient of curvature, Cc = \(\frac{{{D^2}{30}}}{{{D{60;}} \times; {D_{10}}}}\)

Important point:

Typical results of a sieve analysis are shown in the figure below:

(i) Well graded means soil particles of all size are present.

(a) For well-graded gravel, Cu > 4 and 1 ≤ Cc ≤ 3

(b) For well-graded sand, Cu > 6 and 1 ≤ Cc ≤ 3

(ii) Poorly graded or uniformly graded means soil particles of one size are present predominantly.

(iii) Gap graded means soil particles of some size are missing.

(iv) Cu ≈ 1 for uniformly/poorly graded soil.

Question 87

Which of the following cause a decrease in per capita consumption?

  1. AOption (a)

    use of a metering system

  2. BOption (b)

    good quality of water

  3. COption (c)

    better standard of living of the people

  4. DOption (d)

    hotter climate

View answer & explanation

Correct answer

Answer: (a)A.

use of a metering system

Why this answer is correct

Explanation:

The amount of water required to be supplied to satisfy various water needs of an individual is known as per capita demand.

Water;Consumption∝1Metered;water;system{\rm{Water;Consumption}} \propto \frac{1}{{{\rm{Metered;water;system}}}}

Note:

per capita demand decreases with the installation of the metered system as the public becomes more cautious towards their water bill expenditure. 

With an increase in the quality of the water, water consumption increases as the public would consume lesser water if the quality of water is deteriorated.

Water consumption increases with a rise in the standard of living of the people. For e.g. as the standard of living increases, one would install automatic flushing water closet, automatic washing machine, bathtubs, etc and thus water consumption is increased by many folds.

Hotter the climate, higher the water demand.

Question 88

The following data pertain to a sewage sample:

Initial DO = 9.5 mg/l, Final DO = 2 mg/l, Dilution = 1%

The BOD of the given sample is:

  1. AOption (a)

    7.5 mg/l 

  2. BOption (b)

    10 mg/l 

  3. COption (c)

    75 mg/l 

  4. DOption (d)

    750 mg/l 

View answer & explanation

Correct answer

Answer: (d)D.

750 mg/l 

Why this answer is correct

Concept:

Biochemical Oxygen Demand (BOD): 

  • It is defined as the amount of oxygen required by aerobic organisms to break down organic material present in a given sample of water at a certain temperature over a specific period.
  • The BOD value is commonly expressed in “mg of oxygen consumed per liter of the sample during 5 days of incubation at 20℃ i.e. (mg/l) and is often used as a surrogate of the degree of organic pollution of water.

BOD determination through dilution Method:

This method is based upon the determination of dissolved oxygen originally present in an undiluted sample of sewage and the dissolved oxygen present in a diluted sample of sewage after it is subjected to incubation at a constant temperature of 20℃ for a period of 5 days.

The dilution water may be prepared by adding 1.0 ml each of phosphate buffer solution, magnesium sulfate solution, calcium chloride solution, and ferric chloride solution in 1.0 liter of distilled water. For the BOD test, 300ml size bottles are used.

BOD = (DOi - DOf) / Dilution Factor

Dilution;factor=Final;volumeInitial;volume=Pure;water;volume+Sewage;volumeSewage;Volume{\bf{Dilution}};{\bf{factor}} = \frac{{{\bf{Final}};{\bf{volume}}}}{{{\bf{Initial}};{\bf{volume}}}} = \frac{{{\bf{Pure}};{\bf{water}};{\bf{volume}} + {\bf{Sewage}};{\bf{volume}}}}{{{\bf{Sewage}};{\bf{Volume}}}}

Where,

DOi = Dissolved oxygen initial (mg/l), DOf = Dissolved Oxygen final (mg/l)

Note: Amount of pure water should be added to the sewage such that sewage becomes odourless.

Calculation:

Given data,

DOi = 9.5 mg/l, DOf = 2 mg/l and Dilution factor = 1%

∴ BOD = (9.5 - 2) × 100/1 = 750 mg/ℓ

Question 89

The tilt in an aerial photograph is radial from:

  1. AOption (a)

    Nadir point

  2. BOption (b)

    Principal point

  3. COption (c)

    Isocentric point

  4. DOption (d)

    Plumb point

View answer & explanation

Correct answer

Answer: (c)C.

Isocentric point

Why this answer is correct

Explanation

Nadir: The point of the celestial sphere directly opposite to zenith and vertically downward from the observer.

Isocentre: It is the point on the aerial photo platform that directly falls on a line half-way between the Principal point and the Nadir point.

Principal point: The principal point is the point where the perpendicular projected through the center of the lens intersects the photo image.

Plumb point: It is the point where a plumb line dropped from the front nodal point pierces the photograph.

Principle point & Nadir are the same for true verticle aerial image.

Principle point & Nadir are different for a tilted aerial image.

∴ From the figure, we can say as the isocentre is at the centre and principal point and nadir point are at radial distances.

∴ Isocentre is the answer.

Question 90

The staff reading at a distance of 80 m from a level with bubble at its centre is 1.52 m and when it is moved 5 division out of the centre, the reading is 1.60 m. The angular value of the bubble is:

  1. AOption (a)

    20.62”

  2. BOption (b)

    41.25”

  3. COption (c)

    14.55”

  4. DOption (d)

    25.5”

View answer & explanation

Correct answer

Answer: (b)B.

41.25”

Why this answer is correct

Explanation

For bubble tube:

Angular value of bubble is given by:

∝=sD=nlR\propto = \frac{{\rm{s}}}{{\rm{D}}} = \frac{{{\rm{nl}}}}{{\rm{R}}}

For calculating the sensitivity of the bubble tube or angular value of one division

∝′=snD(in;radians)\propto ' = \frac{{\rm{s}}}{{{\rm{nD}}}}\left( {{\rm{in;radians}}} \right)

∝′=snD×206265;(in;seconds)\propto ' = \frac{{\rm{s}}}{{{\rm{nD}}}} \times 206265{\rm{;}}\left( {{\rm{in;seconds}}} \right)

Where

S = Staff reading, D = distance between the instrument and staff,

R = Radius of curvature of the bubble tube,

l = Length of one division of on the bubble tube

Given,

D = 80 m, no. of divisions = 5

 Staff reading when bubble is at centre = 1.52 

 Staff reading when bubble is moved 5 division out = 1.60

 S = 1.60 – 1.52 = 0.08 m

∴;∝′=0.08×2062655×80=41.25;seconds\therefore {\rm{;}} \propto ' = \frac{{0.08 \times 206265}}{{5 \times 80}} = 41.25{\rm{;seconds}}

Question 91

In GIS, the process used for modifying map features to make them clear at a reduced scale is known as

  1. AOption (a)

    Cartographic Generalisation 

  2. BOption (b)

    Database Generalisation

  3. COption (c)

    Topographical Encoding

  4. DOption (d)

    Date Filtering

View answer & explanation

Correct answer

Answer: (a)A.

Cartographic Generalisation 

Why this answer is correct

Explanation:

(i) Cartographic generalization, or map generalization, includes all changes in a map that are made when one derives a smaller-scale map from a larger-scale map or map data or vice versa.

(ii) Since maps are representations of three-dimensional reality, the cartographer must employ abstraction to show only pertinent data in an easy to read and understandable form, and in a usable size. First, data is collected from a variety of sources, such as surveying, remote sensing, and census taking, depending on the project. While surveying and remote sensing give complete data about the subject, a census is itself a representation because it is only a sampling.

(iii) In order to process the material and present it in a usable form, the cartographer must go through a selection process regarding both the map and the material to be represented. Scale selection decides how much detail you can show and the size of the map; then, of the collected data, the decision must be made of what to include on the map. The inclusion of data will vary widely according to purpose and audience: on a road map, elevations are less important, on an elevation map of contour lines, roads are not important.

(iv) There are four aspects to generalization: classification, simplification, exaggeration, and symbolization.

Question 92

An Engineer measured the distance between two locations on a plan having a scale of 1 cm = 50 m as 600 m. Later, however, he found that he used a wrong scale of 1 cm = 30 m to measure the distance. The true distance between the locations is:

  1. AOption (a)

    200 m

  2. BOption (b)

    250 m

  3. COption (c)

    500 m

  4. DOption (d)

    1000 m

View answer & explanation

Correct answer

Answer: (d)D.

1000 m

Why this answer is correct

Explanation

Representative factor

  • It is a map scale in which figures representing units (as cm, inches, or feet) are expressed in the form of the fraction 1 / x (as 1/250,000) or of the ratio 1: x to indicate that one unit on the map represents x units (as 250,000 cm) on the earth's surface.
  • Representative factor = Map distance / Ground distance

​Calculation:

Given,

Wrong scale, 1 cm = 30 m

Correct scale, 1 cm = 50 m

Measured distance = 600 m

R.F of wrong scale = 1 / 3000

R.F of correct scale = 1 / 5000

Corrected length, L=1300015000×600=1000L = \frac{{\frac{1}{{3000}}}}{{\frac{1}{{5000}}}} \times 600 = 1000

The true distance between the two points is 1000 m.

Question 93

Streak of a mineral is

  1. AOption (a)

    Its appearance in diffused light as obtained by rotating it

  2. BOption (b)

    Colour of the powder of a coloured mineral as obtained by rubbing it on a porcelain plate

  3. COption (c)

    Its appearance in thin section as seen under a polarising microscope

  4. DOption (d)

    None of these

View answer & explanation

Correct answer

Answer: (b)B.

Colour of the powder of a coloured mineral as obtained by rubbing it on a porcelain plate

Why this answer is correct

Explanation:

Streak

(i) Streak is the type of test which is used to determine the color of a mineral in powdered form. The colour of a mineral's powder is often a very important property for identifying the mineral.

(ii) The streak test is done by scraping a specimen of the mineral across a piece of unglazed porcelain known as a "streak plate." This can produce a small amount of powdered mineral on the surface of the plate. The powder colour of that mineral is known as its "streak."

Question 94

A road segment of length 1 km scales 6 cm on a vertical photograph. The focal length of the camera is 150 mm. If the terrain is nearly plain, then the flying height of the aircraft will be

  1. AOption (a)

    2500 m

  2. BOption (b)

    25 m

  3. COption (c)

    250 km

  4. DOption (d)

    250 m

View answer & explanation

Correct answer

Answer: (a)A.

2500 m

Why this answer is correct

Concept:

Scale of a vertical Photograph is given by:

Scale;(S)=Map;distanceGround;distance=fH−hScale;\left( S \right) = \frac{{Map;distance}}{{Ground;distance}} = \frac{f}{{H - h}}

Where,

H = Height of exposure station (or the airplane) above the mean sea level = flying height

h = Height of ground above MSL

f = Focal length of the camera

If vertical photograph is taken at Datum scale then (h = 0)

Scale;(S)=Map;distanceGround;distance=fHScale;\left( S \right) = \frac{{Map;distance}}{{Ground;distance}} = \frac{f}{H}

Calculation:

Given,

Map distance = 6 cm

Ground distance = 1 km

Focal length = 150 mm

Map;distanceGround;distance=fH→601=150H\frac{{Map;distance}}{{Ground;distance}} = \frac{f}{H} \to \frac{{60}}{1} = \frac{{150}}{H}

∴ H = 2.5 km = 2500 m

Question 95

If the probable error in single observation is ± 0.04 m and that of the mean is ± 0.01 m, then the number of observations are

  1. AOption (a)

    4

  2. BOption (b)

    10

  3. COption (c)

    16

  4. DOption (d)

    64

View answer & explanation

Correct answer

Answer: (c)C.

16

Why this answer is correct

Concept:

Most probable error: If the error for which there are equal chances that the true error will be less than the probable error and equal chances that the true error will be more than the probable error i.e. each is having the probability of 50%

Most;probable;error;(E)=;±Σv2n−1Most;probable;error;\left( E \right) = ; \pm \sqrt {\frac{{{\rm{\Sigma }}{v^2}}}{{n - 1}}}

Most Probable Error of mean:

Em=En{E_m} = \frac{E}{{\sqrt n }}

Where,

n = Number of observation

Calculation:

Given,

E = ± 0.04

Em = ± 0.01

∵ we know, Em = En\frac{E}{{\sqrt n }}

This relation can be written as,

n=(EEm)2n = {\left( {\frac{E}{{{E_m}}}} \right)^2}

n=(0.040.01)2=16n = {\left( {\frac{{0.04}}{{0.01}}} \right)^2} = 16

Question 96

The tangential method of tacheometry is

  1. AOption (a)

    slower than stadia hair method

  2. BOption (b)

    faster than stadia hair method

  3. COption (c)

    preferred as involves less computations to get reduced distances.

  4. DOption (d)

    preferred as chance of operational error are less compared to stadia hair method 

View answer & explanation

Correct answer

Answer: (a)A.

slower than stadia hair method

Why this answer is correct

Explanation

Moveable hair method 

  • Stadia hair is not fixed but can be moved by means of micrometer screws.
  • The intercept on leveling staff is kept constant and stadia hair interval is variable.
  • The stall is provided with 2 vanes or targets fixed at a known distance apart.
  • The variable stadia distance measured from this value, the required horizontal distance may be found out.
  • It is the slow method as compared to other methods

Fixed hair method

  • In this method distance between hairs is fixed
  • The intercept on leveling staff is variable and stadia hair interval is fixed.
  • The staff intercept value varies with its distance from the instrument, this is most commonly used in tacheometry

Tangential hair method

  • In the tangential hair method the stadia hairs are not used.
  • The readings being taken against horizontal cross hair.
  • It is slower than the stadia hair method.

Question 97

The method adopted for measurement of horizontal angle using theodolite in the case when several angles of well-distributed point/objects are to be measured from the same instrument station is:

  1. AOption (a)

    Repetition

  2. BOption (b)

    Double angle

  3. COption (c)

    Reiteration

  4. DOption (d)

    All of the above

View answer & explanation

Correct answer

Answer: (c)C.

Reiteration

Why this answer is correct

Concept

Measurement of Horizontal Angles

**a) Repetition Method.:**This method is used for very accurate work. In this method, the same angle is added several times mechanically and the correct value of the angle is obtained by dividing the accumulated reading by the no. of repetitions. The No. of repetitions made usually in this method is six, three with the face left and three with the face right. In this way, angles can be measured to a finer degree of accuracy than that obtainable with the least count of the vernier.

b) Reiteration Method. This method is another precise and comparatively less tedious method of measuring the horizontal angles. It is generally preferred when several angles are to be measured at a particular station. This method consists of measuring several angles successively and finally closing the horizon at the starting point. 

Note:

The method of repetition eliminates different errors present in the measurement of a horizontal angle as follows:

  • The errors due to the eccentricity of Vernier’s and centers get eliminated as readings from both the Vernier’s are taken
  • The errors due to inaccurate graduations get eliminated as the readings are observed at different parts of the circle
  • The errors due to lack in the adjustment of line of collimation and the horizontal axis of the instrument get eliminated for considering both face readings
  • Errors due to the inaccurate bisection of the object, eccentric centering, etc are eliminated partially as these get counter-balanced in different observations

Note: The errors due to slip, due to the displacement of station or its signal do not get eliminated and moreover, these errors are cumulative in nature.

Question 98

Two straights AB and BC have the bearing of 70° and 120°, respectively. They are to be connected by a circular curve. The deflection angle will be

  1. AOption (a)

    130°

  2. BOption (b)

    70°

  3. COption (c)

    50°

  4. DOption (d)

    120°

View answer & explanation

Correct answer

Answer: (c)C.

50°

Why this answer is correct

Calculation:

Given,

Bearing of AB = 70° 

Bearing of BC = 120° 

From the figure, we can say that the deflection angle (Δ ) is 

 

Deflection angle, Δ = 120° - 70° = 50°

Question 99

The following boundary condition exists at the wall (y = 0) in a boundary layer:

  1. AOption (a)

    u = U

  2. BOption (b)

    dPdX=−ve\frac {dP}{dX}= -ve

  3. COption (c)

    τ0 = 0

  4. DOption (d)

    u = 0, v = 0

View answer & explanation

Correct answer

Answer: (d)D.

u = 0, v = 0

Why this answer is correct

Concept:

The point of separation may be defined as the limit between forward and reverse flow in the layers very close to the wall i.e. at the point of separation

(∂u∂y)y=0=0{\left( {\frac{{\partial u}}{{\partial y}}} \right)_{y = 0}} = 0

At boundary conditions and the equation ( simplifies since ∂u/∂t = 0.) Assuming Steady-state condition.

  • At the plate surface, there is no flow across it, which implies that v = 0 at y = 0.
  • Due to the viscosity, we have the no-slip condition at the plate. In other words, u = 0 at y = 0.
  • At infinity (outside the boundary layer), away from the plate, we have that u → U as y → infinity

 

Important Points

  • For a given velocity profile, it can be determined whether the boundary has separated, or on the verge of separation, or will not separate from the following condition:

i) (∂u∂y)y=0<0{\left( {\frac{{\partial u}}{{\partial y}}} \right)_{y = 0}} < 0 the flow has separated

ii) (∂u∂y)y=0=0{\left( {\frac{{\partial u}}{{\partial y}}} \right)_{y = 0}} = 0 the flow is on the verge of separation.

ii) (∂u∂y)y=0>0{\left( {\frac{{\partial u}}{{\partial y}}} \right)_{y = 0}} > 0 the flow will not separate or flow will remain attached to the surface.

  • As the y increases the value of (∂u∂y){\left( {\frac{{\partial u}}{{\partial y}}} \right)}is decreases.
  • at y = 0, (∂u∂y){\left( {\frac{{\partial u}}{{\partial y}}} \right)}is maximum, and at  y = δ,  (∂u∂y){\left( {\frac{{\partial u}}{{\partial y}}} \right)} is zero.
  • Hence τ=µ×(∂u∂y)τ=µ\times {\left( {\frac{{\partial u}}{{\partial y}}} \right)}is also maximum at y = 0

Question 100

Hydraulic ram is a pump which works on the principle of

  1. AOption (a)

    Water hammer

  2. BOption (b)

    Centrifugal action

  3. COption (c)

    Reciprocating action

  4. DOption (d)

    Hydraulic press

View answer & explanation

Correct answer

Answer: (a)A.

Water hammer

Why this answer is correct

Explanation:

  • A hydraulic ram is a type of pump which raises water without using any external power.
  • In a hydraulic ram large quantity of water available at a small height is utilized for lifting a small quantity of water to a greater height.
  • The working of the hydraulic ram is based on the small water hammer effect developed in the supply pipeline when the exit valve is suddenly closed.
  • The working of a hydraulic ram is based on the principle of water hammer or inertia pressure developed in the supply pipe.

Question 101

Uniform flow in an open channel exists when the:

  1. AOption (a)

    Channel is frictionless.

  2. BOption (b)

    Channel is non – prismatic.

  3. COption (c)

    Channel is prismatic.

  4. DOption (d)

    Channel is prismatic and the depth of flow is constant along the channel.

View answer & explanation

Correct answer

Answer: (d)D.

Channel is prismatic and the depth of flow is constant along the channel.

Why this answer is correct

Open channel flow is said to be uniform when depth and velocity are same at every section of channel. Hence it follows that uniform flow can occur in prismatic channel.

Question 102

For hydraulically efficient rectangular channel section, ratio of the width to the normal depth:

  1. AOption (a)

    0.5

  2. BOption (b)

    1.0

  3. COption (c)

    2√3 

  4. DOption (d)

    2.0

View answer & explanation

Correct answer

Answer: (d)D.

2.0

Why this answer is correct

Concept:

A channel section is called most efficient if

  • Cost is the minimum for a given discharge.
  • It can pass maximum discharge for a given cross-sectional area, resistance coefficient, and bottom slope.
  • Discharge is maximum when R is becoming maximum and Perimeter becomes minimum as

Rectangular channel section

Area of the flow, A = By

Wetted Perimeter, P = B + 2y

From the area, put the value of B in terms of A and y in the Wetted perimeter equation:

B=AyB = \frac{A}{y}

P=Ay+2yP = \frac{A}{y} + 2y

Since P is minimum for the most efficient section, then

dPdy=0\frac{{dP}}{{dy}} = 0

dPdy=−Ay2+2=0\frac{{dP}}{{dy}} = - \frac{A}{{{y^2}}} + 2 = 0

Putting A = By, we get

B = 2y

By\frac{B}{y} = 2

Hence, For a hydraulically efficient rectangular channel section, the ratio of the width to the normal depth is equal to 2.

Question 103

As the depth of immersion of a vertical plane surface increases, the location of centre of pressure:

  1. AOption (a)

    Moves apart from the centre of gravity of the area

  2. BOption (b)

    Comes closer to the centre of gravity of the area

  3. COption (c)

    Coincide with the centre of gravity of the area

  4. DOption (d)

    Remains unaffected

View answer & explanation

Correct answer

Answer: (b)B.

Comes closer to the centre of gravity of the area

Why this answer is correct

Concept:

The depth of the center of the pressure of lamina is given as,

h=H+;IAHSin2θh = H + ;\frac{I}{{AH}}Si{n^2}\theta

Where I is the MOI about C.G of the lamina.

A = Area of the lamina., H = C.G of lamina., h = Depth of Center of the pressure of lamina.

Above can be written as,

h−H=;IAHh - H = ;\frac{I}{{AH}}   {As plane is vertical, θ = 900}

⇒ h−H∝1Hh - H \propto \frac{1}{H}

All terms on the RHS of equation are positive and therefore, LHS must be positive i.e.

h- H > 0 (always) ⇒ C.P always below the C.G of lamina.

As the lamina is submerged deeper and deeper in water,

H goes on increasing  → (h - H) goes on decreasing → Distance between CP and CG goes on decreasing

∴ CP goes on approaching CG but it never coincides with CG.

It will coincide with CG only when H approaches infinity.

Question 104

A hydraulic jump is formed when 

  1. AOption (a)

    a subcritical flow meets a supercritical flow.

  2. BOption (b)

    a subcritical flow meets a subcritical flow.

  3. COption (c)

    a supercritical flow meets a supercritical flow.

  4. DOption (d)

    a supercritical flow meets a subcritical flow.

View answer & explanation

Correct answer

Answer: (d)D.

a supercritical flow meets a subcritical flow.

Why this answer is correct

Answer:

The hydraulic jump occurs when there is a transition from supercritical flow to subcritical flow and its an example of rapidly varied flow where the flow properties change in a short reach.

Explanation:

Steady and Unsteady flow:

When the flow properties (such as velocity, density, etc.) do not change with respect to the time it is called steady flow and vice versa

Uniform and Non-uniform flow:

When the flow properties (such as velocity, density, etc.) do not change with respect to space i.e. along with the flow, it is called uniform flow and vice versa.

Varied flow:

When the flow properties (such as velocity, density, etc.) change with respect to space i.e. along with the flow, it is called varied flow.

Depending upon the changes it can be either gradually or rapidly varied flow.

Important Note:

Question 105

In a model experiment with weir, if the dimensions of the model weir are reduced by a factor K, the flow rate through the model weir is the following fraction of the flow rate through prototype

  1. AOption (a)

    K5/2

  2. BOption (b)

    K2

  3. COption (c)

    1

  4. DOption (d)

    K-2

View answer & explanation

Correct answer

Answer: (a)A.

K5/2

Why this answer is correct

Explanation:

Flow over weir and notches follow the Froude model law and the Froude model state that the gravity force is the only predominant force in addition to the inertia force, which controls the motion.

(Fr)model = (Fr)prototype

⇒ VmgmLm\frac{{{V_m}}}{{\sqrt {{g_{m{L_m}}}} }} = VpgpLp\frac{{{V_p}}}{{\sqrt {{g_{p{L_p}}}} }}   ……..(i)

It is given in the question, Lm/Lp = Bm/Bp =  K

From (i), VrgrK=1\frac{{{V_r}}}{{\sqrt {{g_{r}K}} }} = 1

Vr=grK{V_r} = \sqrt {{g_{rK}}}

Since in most of the cases gr = 1

So, Vr = √K = (K)1/2

∵ we know, Discharge (Qr) = area × velocity = Ar × Vr

Qr = BmBp;×;LmLp×K1/2\frac{{{B_m}}}{{{B_p}}}; \times ;\frac{{{L_m}}}{{{L_p}}} \times {K^{1/2}}

Qr  = K2 × K1/2

Qr = K5/2

Question 106

In mercury differential manometer used for measuring pressure differences across a venturimeter in a water pipeline, if an error of 2mm has been made in observing a differential head of 10 mm, the percentage error in pressure difference is:

  1. AOption (a)

    12.6

  2. BOption (b)

    25.2

  3. COption (c)

    20

  4. DOption (d)

    30

View answer & explanation

Correct answer

Answer: (c)C.

20

Why this answer is correct

percentage error =ΔpH×100= \frac{{{\rm{\Delta }}p}}{H} \times 100

=210×100=20%= \frac{2}{{10}} \times 100 = 20\%

Question 107

Two identical pipes of length L, diameter D and friction f, are connected in parallel between two points. The length of a single pipe of diameter D and the same friction f, equivalent to the above pair is 

  1. AOption (a)

    2L\sqrt {2L}

  2. BOption (b)

    L/2

  3. COption (c)

    L/√2

  4. DOption (d)

    L/4

View answer & explanation

Correct answer

Answer: (d)D.

L/4

Why this answer is correct

Concept:

Equivalent pipe: It refers to imaginary pipes that are used to determine the head loss and discharge considering that the head loss and discharge in the actual pipe are the same as that of the equivalent pipe.

The length and friction factor of the equivalent pipe need not be equal to the actual pipe.

Given:

When two pipes are connected in parallel which have same dia, length and friction factor then the discharge gets equally distributed.

Head loss given by Darcy weisbach formula,

hL=flV22gD=fLQ212.1;D5{{\rm{h}}_{\rm{L}}} = \frac{{{\rm{fl}}{{\rm{V}}^2}}}{{2{\rm{gD}}}} = \frac{{{\rm{fL}}{{\rm{Q}}^2}}}{{12.1{\rm{;}}{{\rm{D}}^5}}}

When pipes are connected in parallel,

hL=fL;(Q2)212.1;D5=fLQ24×12.1;D5{{\rm{h}}_{\rm{L}}} = \frac{{{\rm{fL;}}{{\left( {\frac{{\rm{Q}}}{2}} \right)}^2}}}{{12.1{\rm{;}}{{\rm{D}}^5}}} = \frac{{{\rm{fL}}{{\rm{Q}}^2}}}{{4 \times 12.1{\rm{;}}{{\rm{D}}^5}}}

Let the equivalent length of pipe having diameter D and same discharge be L’. The head loss through this pipe is given as

h′L=fL′Q212.1;D5{\rm{h}}{{\rm{'}}_{\rm{L}}} = \frac{{{\rm{fL'}}{{\rm{Q}}^2}}}{{12.1{\rm{;}}{{\rm{D}}^5}}}

But for the pipes to be equivalent both head losses should be equal :

∴f;L;Q24×12.1;D5=f;L′Q212.1;D5\therefore \frac{{{\rm{f;L;}}{{\rm{Q}}^2}}}{{4 \times 12.1{\rm{;}}{{\rm{D}}^5}}} = \frac{{{\rm{f;L'}}{{\rm{Q}}^2}}}{{12.1{\rm{;}}{{\rm{D}}^5}}}

⇒L′;=;L4 \Rightarrow {\rm{L';}} = {\rm{;}}\frac{{\rm{L}}}{4}

Question 108

With increase in pressure, the bulk modulus of elasticity 

  1. AOption (a)

    Increases

  2. BOption (b)

    Decreases

  3. COption (c)

    Remains constant

  4. DOption (d)

    Increases and the decreases

View answer & explanation

Correct answer

Answer: (a)A.

Increases

Why this answer is correct

Concept:

  • Fluids also possess elastic characteristics like elastic solids.
  • Compressibility of fluid is quantitatively expressed as the inverse of the bulk modulus of elasticity, K of the fluid.
  • Bulk modulus K is defined as,

\(k = \frac{{stress}}{{strain}} = \frac{{Changeinpressure}}{{\left( {\frac{{Changeinvolume}}{{Original~volume}}} \right)}} = - \frac{{dp}}{{\left( {\frac{{dV}}{V}} \right)}}\)

  • Kwater = 2.06 × 109 N/m2 , Kair = 1.03 × 105 N/m2
  • Bulk modulus (K) of a fluid is not constant, but it increases with increase in pressure.
  • For liquids, K decreases with increase in temperature.
  • For gases, K increases with increase in temperature.

Question 109

The highest velocity for flow of water of viscosity 0.02 poise to be laminar in a 10 mm pipe is: 

  1. AOption (a)

    100 cm/s

  2. BOption (b)

    200 cm/s

  3. COption (c)

    300 cm/s

  4. DOption (d)

    40 cm/s

View answer & explanation

Correct answer

Answer: (d)D.

40 cm/s

Why this answer is correct

Concept:

(i) Reynolds discovered that the occurrence of a laminar and turbulent flow was governed by the relative magnitudes of the inertia and viscous forces.

(ii) Reynolds related the inertia to viscous forces and arrived at a dimensionless parameter,

Re=Inertia;forceViscous;force{R_e} = \frac{{Inertia;force}}{{Viscous;force}}

Re=ρLVμ{R_e} = \frac{{\rho LV}}{\mu }

Where,

ρ = Mass density of fluid

V = mean velocity

L = Characteristics length = Diameter of pipe for pipe flow (D)

μ = Dynamic viscosity

For pipe flow, Re=ρDVμ{R_e} = \frac{{\rho DV}}{\mu }

(iii) The limiting values of Reynolds number for various kind of flow in different flow conditions are given below:

Flow conditionReynolds numberType of flow
Flow in pipes< 2000Laminar
2000 - 4000Transition
> 4000Turbulent
Flow between parallel plate< 1000Laminar
1000 - 2000Transition
> 2000Turbulent
Flow in wide-open channels< 500Laminar
500 – 2000Transition
> 2000Turbulent

Calculation:

 It is given in the question that Flow condition is in laminar condition.

Given,

μ = 0.02 poise = 0.02 × 10-1 Ns/m2  (1 poise = 10-1 Ns/m2)

Diameter of pipe = 10 mm = 10 × 10-3 m

For laminar flow condition, Re = 2000

∵ we know that, Re=ρDVμ{R_e} = \frac{{\rho DV}}{\mu }

2000=103;×;10×10−3;×;V0.02;×10−12000 = \frac{{{{10}^3}; \times ;10 \times {{10}^{ - 3}}; \times ;V}}{{0.02; \times {{10}^{ - 1}}}}

∴ V = 0.4 m/s = 40 cm/s

Question 110

When an irrigation canal is taken over a drainage channel the crossing is called

  1. AOption (a)

    an aqueduct

  2. BOption (b)

    a super passage

  3. COption (c)

    a level crossing

  4. DOption (d)

    none of the above

View answer & explanation

Correct answer

Answer: (a)A.

an aqueduct

Why this answer is correct

Explanation:

Cross-drainage works:

A cross drainage work is a structure that is constructed at the crossing of a canal and a natural drain. To dispose of drainage water without interrupting the continuous canal supply.

Types of cross drainage work:

(i) When canal passes over Drainage:

(a) Aqueduct: HFL of the drain sufficiently below the bottom of canal.

(b) Syphon aqueduct: HFL of the drain is above the bottom of the canal.

 

 

(ii) When canal passes below drainage:

(a) Super passage: FSL of the canal is well below the bottom of the canal

(b) Canal syphon: FSL Of canal is above the bottom of drain.

Question 111

Lacey’s scour depth for a stream carrying a discharge of 3 cumecs per meter width having a silt factor 1.2 is

  1. AOption (a)

    1.32 m

  2. BOption (b)

    2.64 m

  3. COption (c)

    3.96 m 

  4. DOption (d)

    4.32 m

View answer & explanation

Correct answer

Answer: (b)B.

2.64 m

Why this answer is correct

Concept: 

Lacey's scour depth is given by:

R;=;1.35(q2f)13;R; = ;1.35{\left( {\frac{{{q^2}}}{f}} \right)^{\frac{1}{3}}};

Where, q = Discharge per meter width, f = silt factor

Calculations:

Given, q = 3 cumec, f = 1.2

R;=;1.35(321.2)13;=;2.64;mR; = ;1.35{\left( {\frac{{{3^2}}}{1.2}} \right)^{\frac{1}{3}}};=;2.64;m

Important Points

Various formulas deduced by lacey is given below:

1) silt factor ⇒ f=1.76dmm\rm{f = 1.76\sqrt {{d_{mm}}}}

  1. velocity of flow ⇒V=[Qf2140]16V = {\left[ {\frac{{Q{f^2}}}{{140}}} \right]^{\frac{1}{6}}}

3) hydraulic mean depth ⇒R=5V22fR = \frac{{5{V^2}}}{{2f}}

  1. wetted perimeter ⇒ P=4.75QP = 4.75\sqrt Q

Question 112

The discharge passing over an ogee spillway, per unit length of its apex line is proportional to (Where H is head over the apex of its crest):

  1. AOption (a)

    H

  2. BOption (b)

    H2

  3. COption (c)

    H 0.5

  4. DOption (d)

    H 1.5

View answer & explanation

Correct answer

Answer: (d)D.

H 1.5

Why this answer is correct

Concept:

Discharge over an Ogee spillway is given by:

Q=;23Cd2gLHe32Q = ;\frac{2}{3}{C_d}\sqrt {2g} LH_e^{\frac{3}{2}}

He = Total head upstream of the crest.

L = crest width

Cd = coefficient of discharge

C = constant, which is equal to 23Cd2g\frac{2}{3}{C_d}\sqrt {2g}

∴ Discharge Q is proportional to H1.5

Question 113

Lysimeter is used for the measurement of:

  1. AOption (a)

    Interception

  2. BOption (b)

    Infiltration

  3. COption (c)

    Evaporation

  4. DOption (d)

    Evapotranspiration

View answer & explanation

Correct answer

Answer: (d)D.

Evapotranspiration

Why this answer is correct

Humidity: It is a measure of moisture present in the air.

The amount of moisture present in the air when expressed as mass per unit volume is known as absolute humidity.

Humidity is measured by the psychrometer.

Transpiration: It is the process by which water leaves the body of a living plant and reaches atmosphere as water vapour.

Transpiration is measured by phytometer.

Evaporation: It is the process in which a liquid change to the gaseous state at the free surface below the boiling point through the transfer of heat energy.

Evaporimeter measures evaporation.

Evapotranspiration is measured by lysimeter.

Question 114

The relation between duty D in hectares/cumec, depth of water Δ in meters and base period B in days is given by

  1. AOption (a)

    Δ=1.98BD{\rm{\Delta }} = \frac{{1.98{\rm{B}}}}{{\rm{D}}}

  2. BOption (b)

    Δ=8.64BD{\rm{\Delta }} = \frac{{8.64{\rm{B}}}}{{\rm{D}}}

  3. COption (c)

    Δ=5.68BD{\rm{\Delta }} = \frac{{5.68{\rm{B}}}}{{\rm{D}}}

  4. DOption (d)

    Δ=8.64DB{\rm{\Delta }} = \frac{{8.64{\rm{D}}}}{{\rm{B}}}

View answer & explanation

Correct answer

Answer: (b)B.

Δ=8.64BD{\rm{\Delta }} = \frac{{8.64{\rm{B}}}}{{\rm{D}}}

Why this answer is correct

Concept:

Duty: It is the number of hectares of land irrigated for full growth of a given crop by a supply of 1 cumec of water continuously during the entire base period of that crop.

Delta: The total water depth required by a crop to attain its full maturity in its base period.

Base Period: The time period that elapsed for the instant of the showing of crop to the instant of its harvesting is called base period or crop period.

The relation between Duty (D), Delta (Δ) and Base period (B) is given as:

Δ(metres)=8.64BD{\bf{\Delta }}\left( {{\bf{metres}}} \right) = \frac{{8.64B}}{D}

Question 115

The use of unit hydrographs for estimating floods is generally limited to catchments of size less than?

  1. AOption (a)

    5000 km2

  2. BOption (b)

    500 km2

  3. COption (c)

    106 km2

  4. DOption (d)

    5000 ha

View answer & explanation

Correct answer

Answer: (a)A.

5000 km2

Why this answer is correct

Explanation:

Limitation of unit hydrographs:

  • The unit hydrograph for estimating floods is generally limited to the catchment of size less than 5000 km2.
  • Unit hydrograph assumes uniform distribution of rainfall over the catchment.
  • Also the intensity is assumed constant for the duration of rainfall excess.
  • Very large sizes of catchment can give different direct runoff hydrograph (DRH) under otherwise identical situations.

Question 116

According to khosla, to keep the structure safe against piping, exit gradient to be provided should lie between?

  1. AOption (a)

    0.10 and 0.15

  2. BOption (b)

    0.15 and 0.20

  3. COption (c)

    0.20 and 0.26

  4. DOption (d)

    0.25 and 0.30

View answer & explanation

Correct answer

Answer: (b)B.

0.15 and 0.20

Why this answer is correct

Explanation:

Khosla’s Theory: 

It states that seepage of water does not creep along the bottom contour. It moves along a set of streamlines. In order to calculate the uplift pressure and exit, gradient theory takes into account the flow pattern impermeable base of the hydraulic structure.

In Khosla’s theory complex profile of a weir or barrage is broken down into a number of simple profiles and the mathematical solution is obtained for such profiles.

 

Exit gradient (E) according to this theory based on mathematical solutions adopted by Khosla is given

Exit;Gradient;(Ge)=Hd1πλ{\bf{Exit}};{\bf{Gradient}};\left( {{{\bf{G}}_{\bf{e}}}} \right) = \frac{{\bf{H}}}{{\bf{d}}}\frac{1}{{{\bf{\pi }}\sqrt {\bf{\lambda }} }} 

The safe exit gradient should be between 0.15 and 0.20

Question 117

Lateral infiltration is the major drawback in the following type of infiltrometer as

  1. AOption (a)

    Simple tube

  2. BOption (b)

    Double ring

  3. COption (c)

    Sprinkling type

  4. DOption (d)

    Rainfall simulator

View answer & explanation

Correct answer

Answer: (a)A.

Simple tube

Why this answer is correct

Explanation:

Infiltration:

When water table is applied to the surface of the soil, a part of it seeps into the soil. This movement of water through soil is called infiltration.

This infiltration water is used in increasing the moisture of soil up to field capacity and extra water goes down and becomes groundwater.

Measurement of infiltration:

Infiltrometer is a device used to measure rate of water infiltration into the soil.

(i) Flooding type infiltrometer

  • Single ring or simple tube infiltrometer
  • Double ring infiltrometer

(ii) Rainfall simulator

Drawback:

(i) The major drawback of the single ring infiltrometer or simple tube infiltrometer is that the infiltrated water percolates laterally at the bottom of the ring.

(ii) Thus the tube is not truly representing the area through which infiltration is taking place.

Question 118

Isolated storm is represented in a hydrograph with

  1. AOption (a)

    Single peak

  2. BOption (b)

    Multiple peak

  3. COption (c)

    Complex peak

  4. DOption (d)

    None of the above

View answer & explanation

Correct answer

Answer: (a)A.

Single peak

Why this answer is correct

Explanation:

Hydrograph:

(i) A hydrograph is the graphical representation of the discharge flowing in a river at the given location, with the passage of time.

(ii) A hydrograph is capable of representing discharge fluctuation in the river at a given site over a given time period. Hydrograph gives us the peak flow, which is important for the design of hydraulic structure at that site.

(iii) The hydrograph result, due to an isolated storm generally shows the singly peaked skew distribution of discharge and is known as storm hydrograph, flood hydrograph, or simply hydrograph.

(iv) The hydrograph is the response of a given catchment to the rainfall input on the same catchment. Hydrograph consists of surface runoff interflow and baseflow.

Question 119

The deficiency of soil moisture through the earth surface is termed as

  1. AOption (a)

    Rainfall

  2. BOption (b)

    Runoff

  3. COption (c)

    Infiltration

  4. DOption (d)

    Water table

View answer & explanation

Correct answer

Answer: (c)C.

Infiltration

Why this answer is correct

Explanation:

(i) The process of entering rainwater in to soil strata is called infiltration.

(ii) The infiltrated water first meets the soil moisture deficiency if any and excess water moves vertically downwards to reach the groundwater table.

Question 120

 In a CBR test, the load sustained by a remoulded soil specimen at 5 mm penetration is 120 kg. The CBR value of the soil will be:

  1. AOption (a)

    9.2%

  2. BOption (b)

    7.3%

  3. COption (c)

    5.84%

  4. DOption (d)

    2.4%

View answer & explanation

Correct answer

Answer: (c)C.

5.84%

Why this answer is correct

Concept:

CBR test is strength test conducted on the soil by introducing surcharge load at the compaction rate of 1.25 mm per minute on a completely soaked soil sample passing through 20 mm sieve size.

\({\rm{CB}}{{\rm{R}}{\rm{\delta }}} = \frac{{{{\rm{P}}{\rm{\delta }}}{\rm{;of;soil}}}}{{{{\rm{P}}_{\rm{\delta }}}{\rm{;of;standard;crushed;aggregate}}}} \times 100\)

δ = displacement in mm

Pδ = Load corresponding to ‘δ’ settlement

Ps = Load for standard crushed aggregate:

 At 5 mm penetration Standard load Ps = 2055 kg

 At 2.5 mm penetration standard load Ps = 1370 kg

Calculation:

 Given,

 Sustained load at 5 mm penetration = 120 kg 

CBR=;Load;carried;by;specimenload;carried;by;standard;specimen×100CBR = ;\frac{{{\rm{Load;carried;by;specimen}}}}{{{\rm{load;carried;by;standard;specimen}}}} \times 100

At 5 mm penetration, CBR=;1202055×100=5.84%CBR = ;\frac{{120}}{{2055}} \times 100 = 5.84\%

Question 121

The type of transition curve that is generally provided on hill road is

  1. AOption (a)

    Circular

  2. BOption (b)

    Cubic parabola

  3. COption (c)

    Lemniscate

  4. DOption (d)

    Spiral

View answer & explanation

Correct answer

Answer: (d)D.

Spiral

Why this answer is correct

Explanation:

Transitions curve:

(i) When a vehicle traveling on a straight road enters into a horizontal curve instantaneously, it will cause discomfort to the driver. To avoid this, it is required to provide a transition curve. This may be provided either between a tangent and a circular curve or between two branches of a compound or reverse curve.

Different types of transition curve:

The types of transition curves commonly adopted in horizontal alignment highway are

(i) Spiral or clothoid

(ii) Bernoulli’s Lemniscate

(iii) Cubic parabola

(a) All the three curves follow almost the same path up to deflection angle of 4°, and practically there is no significant difference between even up to 9°. In all these curves, the radius decreases as the length increases.

(b) According to IRC ideal shape for transition curve is spiral because rate of change of radial acceleration remains constant. Generally, spiral curve provided on hilly road.

(c) Cubic parabola is provided for the railway.

Question 122

It is common practice to design a highway to accommodate the traffic volume corresponding to

  1. AOption (a)

    30th hour

  2. BOption (b)

    Peak hour

  3. COption (c)

    Average Daily Traffic

  4. DOption (d)

    15-min peak period

View answer & explanation

Correct answer

Answer: (a)A.

30th hour

Why this answer is correct

The design hourly volume is the thirtieth highest hourly traffic count for the design year.

 It is that hourly volume which will be exceeded only 29 times in a year for a particular volume and all the other traffic volume data will be lesser than that.

15min⁡.PHF=Hourly;Traffic;Volume(6015)×V15(max)15\min .PHF = \frac{{Hourly;Traffic;Volume}}{{\left( {\frac{{60}}{{15}}} \right) \times {V_{15}}\left( {max} \right)}}

Average;Daily;traffic;(ADT)=Number;of;vehicle;crossing;a;particular;section;in;a;week;or;month;but;less;than;a;year730Average;Daily;traffic;\left( {ADT} \right) = \frac{{Number;of;vehicle;crossing;a;particular;section;in;a;week;or;month;but;less;than;a;year}}{{\frac{7}{{30}}}}

Question 123

The safe speed on transition curve of B.G. track can be calculated by using formula :

  1. AOption (a)

    4.35(R−67)4.35 \sqrt{(R-67)}

  2. BOption (b)

    4.4×(R−67)4.4 \times\sqrt{(R-67)}

  3. COption (c)

    3.65×(R−6)3.65 \times \sqrt{(R-6)}

  4. DOption (d)

    None of the above

View answer & explanation

Correct answer

Answer: (a)A.

4.35(R−67)4.35 \sqrt{(R-67)}

Why this answer is correct

Concept:

As per martin’s formula, safe speed can be given as follow:

a) For low speed (< 100 kmph)

(i) On a transition Curve:

Depending on the radius of the curve (in meter) and the speed for transition curves can be given by Martin’s Formula,

For Broad Gauge and Meter Gauge:

The safe speed on the transition curve

Vs=4.35R−67{V_s} = 4.35\sqrt {R - 67}  km/hr

or

Vs=4.4R−70{V_s} = 4.4\sqrt {R - 70}

For Narrow Gauge:

The safe speed on the transition curve

Vs=3.65R−6{V_s} = 3.65\sqrt {R - 6}  km/hr

Subjected to a maximum of 50 kmph.

(ii) On a non-transitional curve: 80% of the above-given speeds for respective gauges.

b) For High speed (> 100 kmph)

V=4.58R{\rm{V}} = 4.58\sqrt R kmph

Question 124

The maximum limit of super elevation on B.G. track in India is

  1. AOption (a)

    76.2 mm

  2. BOption (b)

    83.2 mm

  3. COption (c)

    101.6 mm

  4. DOption (d)

    165.1 mm

View answer & explanation

Correct answer

Answer: (d)D.

165.1 mm

Why this answer is correct

Explanation:

Superelevation:

(i) It is the difference between the height of outer rail and inner rail on curve.

(ii) It is also known as cant.

(iii) Inner rail is taken as the reference rail and w.r.t. inner rail, outer rail is raised.

Formula for superelevation:

e=GV2127Re = \frac{{G{V^2}}}{{127R}}

Where,

G = Gauge

V = Speed (in kmph)

R = Radius (in m)

Maximum value of cant (emax):

B.G. TrackM.G.N.G.
< 120 kmph> 120 kmph
emax (actual)16.5 cm18.5 cm10.0 cm7.6 cm

So, emax for BG Track is 16.5 cm = 165 mm

Objective of Providing a superelevation:

(i) To neutralize the effect of centrifugal force.

(ii) Achieve equal distribution of wheel loads.

(iii) To improve the comfort level of passengers.

(iv) To avoid jerk when rolling stock moves from a straight section to a curved section.

Question 125

As per Indian Road Congress (IRC) recommendation, minimum radius of horizontal curve on urban roads in plain terrain when the design speed is 60 Km/h and super elevation is limited to 7% is:

  1. AOption (a)

    120 m

  2. BOption (b)

    125 m

  3. COption (c)

    128.85 m

  4. DOption (d)

    135 m

View answer & explanation

Correct answer

Answer: (c)C.

128.85 m

Why this answer is correct

Explanation

Minimum Radius =(Minimum;Design;Speed)2127×(e+f)= \frac{{{{\left( {Minimum;Design;Speed} \right)}^2}}}{{127 \times \left( {e + f} \right)}}

Ruling Minimum Radius =(Ruling;Design;Speed)2127×(e+f)= \frac{{{{\left( {Ruling;Design;Speed} \right)}^2}}}{{127 \times \left( {e + f} \right)}}

Minimum Radius beyond which there is no need to provide super-elevation

=Design;Speed225×Camber= \frac{{Design;Speed}}{{225 \times Camber}}

Calculations:

Given, 

 V = 60 kmph , e = 0.07 

 we know f = 0.15

Minimum Radius =(Design;Speed)2127×(0.07+0.15)= \frac{{{{\left( {Design;Speed} \right)}^2}}}{{127 \times \left( {0.07 + 0.15} \right)}}

Minimum Radius =(60)2127×(0.07+0.15)=128.85;m= \frac{{{{\left( {60} \right)}^2}}}{{127 \times \left( {0.07 + 0.15} \right)}} = 128.85;m

 

Important Points

Information about Design speed:

Class of RoadTerrain
PlainRolling
RulingMinimumRulingMinimum
NH/SH100808065
MDR80656550
ODR65505040
VR50404035

 

where,

NH = National Highway

SH = State Highway

MDR = Main District Road

ODR = Ordinary District Road

VR = Village Road

125 questions in the full paper