Previous Year Paper

RRB Technician Grade III Official Paper (Held On: 23 Dec, 2024 Shift 2) (Previous Year Paper)

Held in 2024

100 questions90 minutes
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Full Test (100 questions)

Question 1

The pollen needs to be transferred from the stamen to the stigma. If this transfer of pollen occurs in the same flower, this phenomenon is known as:

  1. AOption (a)

    fertilisation

  2. BOption (b)

    cross-pollination

  3. COption (c)

    spore formation

  4. DOption (d)

    self-pollination

View answer & explanation

Correct answer

Answer: (d)D.

self-pollination

Why this answer is correct

The correct answer is self-pollination.

Key Points

  • Self-pollination is the transfer of pollen grains from the stamen to the stigma of the same flower or another flower on the same plant.
  • This process ensures genetic consistency and can occur in both monocots and dicots.
  • It is a form of sexual reproduction in plants but does not promote genetic diversity as cross-pollination does.
  • Plants that predominantly self-pollinate include wheat, rice, and tomatoes.
  • Mechanisms such as cleistogamy (flowers that never open) ensure self-pollination in some plant species.

Additional Information

  • Cross-pollination
  • It involves the transfer of pollen from the stamen of one flower to the stigma of another flower, often requiring external agents like wind, water, or animals.
  • Cross-pollination promotes genetic diversity and can lead to hybrid vigor in plants.
  • Common examples include apples, pumpkins, and many types of flowers.
  • Fertilization
  • It is the process following pollination where male gametes from pollen grains unite with female gametes (ovules) to form a zygote.
  • Fertilization results in the formation of seeds and fruit in flowering plants.
  • It can occur in both self-pollinated and cross-pollinated plants.
  • Spore Formation
  • It is an asexual reproductive process found in fungi, algae, and some plants like ferns and mosses.
  • Spores are usually single-celled and can develop into a new organism without the need for fertilization.
  • Spores are highly resistant to environmental stresses and can remain dormant for extended periods.
  • Stamen and Stigma
  • The stamen is the male reproductive part of a flower, consisting of the anther and filament.
  • The stigma is the female reproductive part of a flower that receives pollen during pollination.
  • Both stamen and stigma are essential for sexual reproduction in flowering plants.

Question 2

What is the value of power if a man does 50 J of work in 10 s ?

  1. AOption (a)

    5 W

  2. BOption (b)

    500 W

  3. COption (c)

    50 W

  4. DOption (d)

    0.5 W

View answer & explanation

Correct answer

Answer: (a)A.

5 W

Why this answer is correct

The correct answer is 5 W.

Key Points

  • The power (P) is calculated using the formula P=WtP=\frac{W}{t}, where W is the work done and t is the time taken.
  • Given: Work Done(W)= 50 Joules Time Taken(t)= 10 seconds.
  • Substituting the values, P=50J10s=5WattsP=\frac{50J}{10s}=5Watts.
  • Power is measured in Watts (W), which is equal to one Joule per second.

Additional Information

  • Work (W)
  • Work is defined as the energy transferred to or from an object via the application of force along a displacement.
  • The SI unit of work is the Joule (J).
  • Work is calculated as W=F.d.cos(θ)W=F.d.cos(\theta ), where F is the force applied, d is the displacement, and θ is the angle between the force and the displacement direction.
  • Time (t)
  • Time is a measure of the duration of an event.
  • In the context of power calculation, time is the duration over which the work is done.
  • The SI unit of time is the second (s).
  • Power (P)
  • Power is the rate at which work is done or energy is transferred.
  • The SI unit of power is the Watt (W), which is equivalent to one Joule per second.
  • Power can also be calculated using the formula P=V.IP=V.I in electrical contexts, where V is voltage and I is current.
  • Energy
  • Energy is the capacity to do work.
  • It exists in various forms such as kinetic, potential, thermal, electrical, chemical, and nuclear energy.
  • Energy is conserved in all processes; it can neither be created nor destroyed, only converted from one form to another (First Law of Thermodynamics).

Question 3

How are three resistances 3 Ω, 4 Ω, and 6 Ω connected in combination, so that their total resistance will be 13 Ω?

  1. AOption (a)

    All in series

  2. BOption (b)

    Does not depend on any combination

  3. COption (c)

    3 Ω in series with 6 Ω and 4 Ω in parallel

  4. DOption (d)

    All in parallel

View answer & explanation

Correct answer

Answer: (a)A.

All in series

Why this answer is correct

The correct answer is All in series.

Key Points

  • When resistances are connected in series, the total resistance is the sum of individual resistances.
  • The formula for total resistance in series is: Rtotal=R1+R2+R3R_{total}=R_1+R_2+R_3.
  • For resistances of 3Ω, 4Ω, and 6Ω in series, the total resistance is 3 + 4 + 6 = 13Ω.
  • In a series circuit, the current flowing through each resistor is the same.
  • Resistors in series provide a higher total resistance than any individual resistor.

Additional Information

  • Parallel Circuit:
  • In a parallel circuit, the total resistance is less than the smallest resistor in the circuit.
  • The formula for total resistance in parallel is 1Rtotal=1R1+1R2+1R3\frac{1}{R_{total}}=\frac{1}{R_1}+\frac{1}{R_2}+\frac{1}{R_3}.
  • Parallel circuits are used to reduce the overall resistance and to provide the same voltage across all components.
  • Ohm's Law:
  • Ohm's Law states that V=IRV=IR, where V is voltage, I is current, and R is resistance.
  • This law is fundamental in understanding the behavior of electrical circuits.
  • Applications of Resistors:
  • Resistors are used to control current flow in circuits.
  • They are essential in setting voltage levels and for timing applications in electronic devices.

Question 4

The Union Budget 2024-25 outlines a comprehensive strategy to achieve 'Viksit Bharat' by focusing on _______ key priorities that aim to create abundant opportunities for all citizens. Together, these initiatives are designed to propel India towards a developed nation status. 

  1. AOption (a)

    five 

  2. BOption (b)

    eight 

  3. COption (c)

    ten 

  4. DOption (d)

    nine

View answer & explanation

Correct answer

Answer: (d)D.

nine

Why this answer is correct

The correct answer is nine.

Key Points

  • The Union Budget 2024-25 focuses on nine key priorities to achieve the goal of 'Viksit Bharat' or Developed India.
  • These priorities aim to create abundant opportunities for all citizens, ensuring inclusive growth and development.
  • The strategy is designed to propel India towards becoming a developed nation by addressing critical areas such as infrastructure, healthcare, education, and innovation.
  • Key initiatives include investments in renewable energy, digital infrastructure, skill development, and social welfare programs.

Additional Information

  • Union Budget
  • The Union Budget is the annual financial statement presented by the Government of India, detailing its revenue and expenditure for the upcoming fiscal year.
  • It is presented by the Finance Minister in Parliament and is a key policy document outlining the government's economic strategy and priorities.
  • The budget includes proposals for taxation, government spending, and allocation of resources to various sectors.
  • It plays a crucial role in shaping the economic and social policies of the country.
  • Inclusive Growth
  • Inclusive growth refers to economic growth that is distributed fairly across society and creates opportunities for all, particularly the disadvantaged.
  • It aims to reduce poverty and inequality by ensuring that the benefits of growth reach every section of society.
  • Policies for inclusive growth typically focus on education, healthcare, social protection, and employment generation.
  • This approach ensures sustainable development by promoting social stability and equity.
  • Infrastructure Development
  • Infrastructure development involves the construction and improvement of foundational services such as transportation, energy, water supply, and telecommunications.
  • It is critical for economic growth as it enhances productivity, reduces costs, and improves the quality of life for citizens.
  • Investment in infrastructure is a key priority for governments to boost economic activity and create jobs.
  • Modern infrastructure also supports sustainable development by integrating green technologies and practices.

Question 5

The third edition of the joint military exercise ‘AUSTRAHIND’ is being conducted between the armies of which two countries? 

  1. AOption (a)

    India and Australia

  2. BOption (b)

    India and New Zealand

  3. COption (c)

    India and Singapore

  4. DOption (d)

    India and Japan

View answer & explanation

Correct answer

Answer: (a)A.

India and Australia

Why this answer is correct

The correct answer is India and Australia.

Key Points

  • The joint military exercise 'AUSTRAHIND' is conducted between the armies of India and Australia.
  • The third edition of this exercise focuses on enhancing military cooperation and interoperability between the two nations.
  • 'AUSTRAHIND' aims to improve tactical skills, practice joint operations, and increase mutual understanding.
  • The exercise includes various drills, counter-terrorism operations, and humanitarian assistance operations.

Additional Information

  • ​The Comprehensive Strategic Partnership (CSP) between India and Australia, established in June 2020, further strengthens bilateral defense ties.
  • Joint military exercises improve coordination and interoperability between the armed forces of participating nations.
  • They provide an opportunity to learn from each other’s best practices and operational experiences.
  • The first edition of 'AUSTRAHIND' was conducted in 2016 with the aim of bolstering defense cooperation between India and Australia.

Question 6

JGLI is related to NKPM in a certain way based on the English alphabetical order. In the same way, PMRO is related to TQVS. To which of the following options is MJOL related, following the same logic?

  1. AOption (a)

    NQSP

  2. BOption (b)

    NQPS

  3. COption (c)

    QNSP

  4. DOption (d)

    QNPS

View answer & explanation

Correct answer

Answer: (c)C.

QNSP

Why this answer is correct

The logic followed here is:

For, JGLI is related to NKPM

For, PMRO is related to TQVS

Similarly, 

MJOL related ?

Hence, the correct answer is "Option 3".

Question 7

Pranay starts from Point A and drives 45 km towards North. He then takes a right turn, drives 35 km, turns right and drives 75 km. He then takes a right turn and drives 25 km. He takes a final right turn, drives 30 km and stops at Point P. How far (shortest distance) and towards which direction should he drive in order to reach Point A again?

(All turns are 90 degree turns only unless otherwise specified.)

  1. AOption (a)

    10 km towards North

  2. BOption (b)

    10 km towards West

  3. COption (c)

    10 km towards South

  4. DOption (d)

    10 km towards East

View answer & explanation

Correct answer

Answer: (b)B.

10 km towards West

Why this answer is correct

Given:

 Pranay starts from Point A and drives 45 km towards North.

He then takes a right turn, drives 35 km, turns right and drives 75 km.

He then takes a right turn and drives 25 km.

He takes a final right turn, drives 30 km and stops at Point P.

Thus,  he drive 10 km towards West in order to reach Point A again.

Hence, the correct answer is "Option 2".

Question 8

For a candidate to clear an examination, he/she must score 55% marks. If he/she gets 120 marks and fails by 78 marks, the total marks of the examination is:

  1. AOption (a)

    400

  2. BOption (b)

    360

  3. COption (c)

    320

  4. DOption (d)

    300

View answer & explanation

Correct answer

Answer: (b)B.

360

Why this answer is correct

Shortcut Trick

Passing Marks = Marks Obtained + Failing Marks = 120 + 78 = 198

According to the question, 55% = 198

1% = 198 ÷ 55 = 3.6

100% (Total Marks) = 3.6 × 100 = 360

∴ The correct answer is 360.

Alternate Method

Given:

Marks scored by the candidate = 120

Marks by which the candidate failed = 78

Minimum Passing Percentage = 55%

Calculations:

⇒ Let the Total Marks of the examination be x.

⇒ Passing Marks = Marks Obtained + Failing Marks

⇒ Passing Marks = 120 + 78 = 198

⇒ According to the condition, Passing Marks = 55% of Total Marks

⇒ 198 = (55 ÷ 100) × x

⇒ x = (198 × 100) ÷ 55

⇒ x = 19800 ÷ 55

⇒ x = 360

∴ The correct answer is 360.

Additional Information

Passing Marks Calculation

Passing Marks = Obtained Marks + Failure Margin. Conversely, if a student passes with extra marks, Passing Marks = Obtained Marks − Extra Marks.

Percentage to Value

If a% of a number is N, then the number is (N ÷ a) × 100.

Total Marks Concept

The Maximum Marks or Total Marks in any exam-based problem is always considered as 100% for calculation purposes.

Question 9

Two trains 135 m and 155 m in length, respectively, are running in opposite directions, one at the rate of 80 km/h and the other at the rate of 65 km/h. In how much time will they be completely clear of each other from the moment they meet?

  1. AOption (a)

    7.2 sec

  2. BOption (b)

    7.5 sec

  3. COption (c)

    6.5 sec

  4. DOption (d)

    6.8 sec

View answer & explanation

Correct answer

Answer: (a)A.

7.2 sec

Why this answer is correct

Shortcut Trick

When two objects move in opposite directions, their Relative Speed is the sum of their individual speeds.

Total Distance to cover = Sum of lengths of both trains = 135 + 155 = 290 m.

Relative Speed = 80 + 65 = 145 km/h = 145 × (5/18) m/s.

Time = Distance ÷ Relative Speed = 290 ÷ (145 × 5/18) = (290 × 18) ÷ (145 × 5) = 2 × 18 ÷ 5 = 36 ÷ 5 = 7.2 sec.

∴ The correct answer is 7.2 sec.

Alternate Method

Given: Length1 = 135 m, Length2 = 155 m, Speed1 = 80 km/h, Speed2 = 65 km/h.

Formula Used: Time = (Total Distance) ÷ (Relative Speed)

⇒ Total Length = 135 + 155 = 290 m

⇒ Relative Speed = (80 + 65) × (5/18) m/s

⇒ Relative Speed = 145 × 5 ÷ 18 = 725 ÷ 18 m/s

⇒ Time taken = 290 ÷ (725 ÷ 18)

⇒ Time taken = (290 × 18) ÷ 725

⇒ Time taken = 5220 ÷ 725 = 7.2 sec

∴ The correct answer is 7.2 sec.

Additional Information

Relative Speed Concepts

Same Direction: Srel = S1 − S2 | Opposite Direction: Srel = S1 + S2.

Unit Conversion

To convert km/h to m/s, multiply by 5/18. To convert m/s to km/h, multiply by 18/5.

Train Crossing Objects

When crossing another train, distance = sum of lengths. When crossing a pole/man, distance = length of the train.

Question 10

Which of the following reactions is an example of decomposition reaction? 

  1. AOption (a)

    Silver chloride turns grey in sunlight

  2. BOption (b)

    Burning of natural gas

  3. COption (c)

    Formation of water from H2(g) and O2(g)

  4. DOption (d)

    Burning of coal

View answer & explanation

Correct answer

Answer: (a)A.

Silver chloride turns grey in sunlight

Why this answer is correct

The correct answer is Silver chloride turns grey in sunlight.

Key Points

  • A decomposition reaction is a type of chemical reaction where one compound breaks down into two or more simpler substances.
  • The reaction for silver chloride (AgCl) decomposing in sunlight can be represented as: 2AgCl(s) → 2Ag(s) + Cl2(g).
  • This reaction is characterized by the breakdown of silver chloride into silver and chlorine gas.
  • Silver chloride turns grey in sunlight due to the formation of metallic silver, which is grey in color.

Additional Information

  • Decomposition Reaction
  • It is a chemical reaction in which a single compound breaks down into two or more elements or new compounds.
  • Decomposition reactions often require an input of energy in the form of heat, light, or electricity.
  • Examples include the electrolysis of water and thermal decomposition of calcium carbonate.
  • Thermal Decomposition
  • It is a type of decomposition reaction where a compound is broken down into simpler substances by heating.
  • Example: Calcium carbonate decomposes into calcium oxide and carbon dioxide when heated.
  • Photochemical Reaction
  • These reactions are initiated by the absorption of light.
  • An example is the decomposition of silver chloride in sunlight.
  • Redox Reaction
  • Redox reactions involve the transfer of electrons between two species.
  • These reactions include both oxidation and reduction processes.

Question 11

Based on the English alphabetical order, three of the following four letter-clusters are alike in a certain way and thus form a group. Which letter-cluster does not belong to that group?

(Note: The odd one out is not based on the number of consonants / vowels or their position in the letter-cluster.)

  1. AOption (a)

    FUT

  2. BOption (b)

    CEG

  3. COption (c)

    JLN

  4. DOption (d)

    TVX

View answer & explanation

Correct answer

Answer: (a)A.

FUT

Why this answer is correct

The logic followed here is:

Option 1) FUT

Option 2) CEG

Option 3) JLN

Option 4) TVX

Hence, the correct answer is "Option 1".

Question 12

At what rate (in percentage) per annum will a sum of money double itself in 16 years on simple interest?

  1. AOption (a)

    12.5%

  2. BOption (b)

    2.5%

  3. COption (c)

    6.25%

  4. DOption (d)

    5.6%

View answer & explanation

Correct answer

Answer: (c)C.

6.25%

Why this answer is correct

Shortcut Trick

To double a sum of money, the Simple Interest must be equal to the Principal (100%).

Shortcut Formula: Rate × Time = 100 (when sum doubles)

Rate = 100 ÷ 16

Rate = 6.25%

∴ The correct answer is 6.25%.

Alternate Method

Given:

Let Principal (P) = ₹100

Since the sum doubles, Amount (A) = 2 × 100 = ₹200

Time (T) = 16 years

Formula Used:

Simple Interest (SI) = Amount − Principal

SI = (P × R × T) ÷ 100

Calculations:

⇒ SI = 200 − 100 = ₹100

⇒ 100 = (100 × R × 16) ÷ 100

⇒ 100 = R × 16

⇒ R = 100 ÷ 16

⇒ R = 6.25%

∴ The correct answer is 6.25%.

Additional Information

Sum 'n' times itself

If a sum becomes 'n' times itself in T years at simple interest, the rate R is given by: R = [(n − 1) × 100] ÷ T.

Simple Interest vs Compound Interest

In SI, the interest remains constant every year, whereas in CI, interest is calculated on the accumulated amount of previous years.

Rule of 72

A quick way to estimate the time to double money at Compound Interest is T ≈ 72 ÷ Rate.

Question 13

Anu is two years older than Kanu, who is twice as old as Tanu. If the total of their ages is 32, then what is the difference in age of Anu and Tanu?

  1. AOption (a)

    8 years

  2. BOption (b)

    7 years

  3. COption (c)

    14 years

  4. DOption (d)

    12 years

View answer & explanation

Correct answer

Answer: (a)A.

8 years

Why this answer is correct

Shortcut Trick

Assume Tanu age = 1 unit.

Then Kanu age = 2 units and Anu age = 2 units + 2 years.

Sum = 1 + 2 + 2 + 2 years = 5 units + 2 years = 32 years ⇒ 5 units = 30 years ⇒ 1 unit = 6 years.

Difference (Anu − Tanu) = (2 units + 2) − (1 unit) = 1 unit + 2 = 6 + 2 = 8 years.

∴ The correct answer is 8 years.

Alternate Method

Given:

Let Tanu age = x years.

Kanu age = 2x years.

Anu age = (2x + 2) years.

Calculations:

⇒ Total Age = x + 2x + (2x + 2) = 32

⇒ 5x + 2 = 32

⇒ 5x = 30

⇒ x = 6 years (Tanu age)

⇒ Anu age = 2(6) + 2 = 12 + 2 = 14 years.

⇒ Age difference = 14 − 6 = 8 years.

∴ The correct answer is 8 years.

Additional Information

Ratio and Proportion in Ages

If the ratio of ages of A and B is a : b and the sum is S, then A age = (a ÷ (a + b)) × S.

Age Difference Property

The difference between the ages of two persons remains constant throughout their lives, regardless of the number of years passed.

Question 14

Refer to the given series and answer the question that follows (all numbers are single-digit numbers only, and all counting is to be done from left to right).

(Left) 9 1 1 5 7 8 0 4 5 9 9 4 6 9 4 1 6 6 8 1 4 3 5 0 2 1 9 8 6 1 (Right)

How many such odd digits are there, each of which is immediately preceded by a perfect square and immediately followed by an odd digit? (Note: 1 will be considered as a perfect square.)

  1. AOption (a)

    3

  2. BOption (b)

    2

  3. COption (c)

    1

  4. DOption (d)

    5

View answer & explanation

Correct answer

Answer: (d)D.

5

Why this answer is correct

Given number series: 9 1 1 5 7 8 0 4 5 9 9 4 6 9 4 1 6 6 8 1 4 3 5 0 2 1 9 8 6 1

According to the question,

Condition:  perfect square - odd number - odd number

9 1 1 5 7 8 0 4 5 9 9 4 6 9 4 1 6 6 8 1 4 3 5 0 2 1 9 8 6 1

Thus, there are 5 odd numbers which are preceded by a perfect square and immediately followed by an odd digit.

911, 115, 157, 459, and 435.

Hence, "Option 4" is the correct answer.

Question 15

Which body part in the human body is composed of stratified squamous epithelium?

  1. AOption (a)

    Lining of the kidney tubules

  2. BOption (b)

    Skin

  3. COption (c)

    Lining of the intestine

  4. DOption (d)

    Oesophagus

View answer & explanation

Correct answer

Answer: (b)B.

Skin

Why this answer is correct

The correct answer is Skin.

Key Points

  • Stratified squamous epithelium is a type of epithelial tissue that consists of multiple layers of flat cells.
  • The primary function of this tissue is to provide protection against mechanical stress, dehydration, and microbial invasion.
  • The outermost layer of the skin, known as the epidermis, is composed of stratified squamous epithelium.
  • These cells in the skin are keratinized, meaning they contain keratin, a protein that helps in waterproofing and providing strength.
  • Stratified squamous epithelium is also found in other parts of the body, such as the oesophagus and oral cavity, but the skin's epidermis is the most prominent example.

Additional Information

  • Epithelial Tissue
  • Epithelial tissues are one of the four basic types of tissues in the body, along with connective tissue, muscle tissue, and nervous tissue.
  • They cover the body surfaces, line body cavities, and form glands.
  • Epithelial tissues are classified based on the number of layers (simple or stratified) and the shape of the cells (squamous, cuboidal, or columnar).
  • Keratin
  • Keratin is a type of protein found in the skin, hair, and nails.
  • It provides structural strength and helps protect cells from damage or stress.
  • Oesophagus
  • The oesophagus is a muscular tube that connects the throat (pharynx) with the stomach.
  • It is lined with non-keratinized stratified squamous epithelium, which provides protection from abrasion due to food passage.
  • Skin Layers
  • The skin is composed of three main layers: the epidermis, dermis, and hypodermis.
  • The epidermis is the outermost layer, primarily made up of keratinized stratified squamous epithelium.
  • The dermis lies beneath the epidermis and contains connective tissue, blood vessels, and nerve endings.
  • The hypodermis, also known as the subcutaneous layer, contains fat and connective tissue that insulates and cushions the body.

Question 16

Which of the following options should come in place of the question mark (?) in the given series based on the English alphabetical order?

FJN, IMQ, LPT, OSW, ?

  1. AOption (a)

    SUY

  2. BOption (b)

    RUZ

  3. COption (c)

    RUY

  4. DOption (d)

    RVZ

View answer & explanation

Correct answer

Answer: (d)D.

RVZ

Why this answer is correct

The logic followed here is:

Logic: +3 in the each letter.

Hence, the correct answer is "Option 4".

Question 17

Pipe A is 3 times faster than pipe B. Both pipes together fill a tank in 36 min. How much time will pipe A alone take to fill the tank?

  1. AOption (a)

    156 min

  2. BOption (b)

    80 min

  3. COption (c)

    100 min

  4. DOption (d)

    48 min

View answer & explanation

Correct answer

Answer: (d)D.

48 min

Why this answer is correct

Shortcut Trick

Ratio of efficiency A : B = 3 : 1

Total efficiency = 3 + 1 = 4 units/min

Total work = Total efficiency × Total time = 4 × 36 = 144 units

Time taken by A alone = Total work ÷ Efficiency of A = 144 ÷ 3 = 48 min

∴ The correct answer is 48 min.

Alternate Method

Given: Efficiency of Pipe A is 3 times that of Pipe B. Time taken together = 36 min.

Formula Used: Work = Efficiency × Time; Time = Work ÷ Efficiency

PipeEfficiency (units/min)Total WorkTime (min)
Pipe A3144144 ÷ 3 = 48
Pipe B1144 ÷ 1 = 144

⇒ Let the efficiency of Pipe B be 1 unit/min.

⇒ Efficiency of Pipe A = 3 × 1 = 3 units/min.

⇒ Combined efficiency of (A + B) = 3 + 1 = 4 units/min.

⇒ Total capacity of the tank = 4 units/min × 36 min = 144 units.

⇒ Time taken by Pipe A alone = 144 units ÷ 3 units/min = 48 min.

∴ The correct answer is 48 min.

Additional Information

Efficiency and Time Relationship

The time taken to complete a work is inversely proportional to the efficiency. If Pipe A is 3 times faster than Pipe B, the ratio of time taken is 1 : 3.

Pipes and Cisterns Rule

If two pipes A and B fill a tank in x and y minutes respectively, then together they fill it in (x × y) ÷ (x + y) minutes.

Inlet and Outlet Concept

Inlet pipes carry positive efficiency, while outlet (leak) pipes carry negative efficiency when calculating total work per unit time.

Question 18

Six people - Adam, Brad, Clara, David, Emily and Farah - are sitting in a straight line, facing north. Only one person sits to the left of Clara. Only one person sits between Clara and Brad. David sits second to the right of Emily. Adam is neither an immediate neighbour of Clara nor sits at the extreme end of the line.

Who sits at the extreme right end of the line?

  1. AOption (a)

    Farah

  2. BOption (b)

    David

  3. COption (c)

    Brad

  4. DOption (d)

    Emily

View answer & explanation

Correct answer

Answer: (a)A.

Farah

Why this answer is correct

Given: Six people - Adam, Brad, Clara, David, Emily and Farah - are sitting in a straight line, facing north.

Only one person sits to the left of Clara. Only one person sits between Clara and Brad.

David sits second to the right of Emily. Adam is neither an immediate neighbour of Clara nor sits at the extreme end of the line.

Thus, Farah sits at the extreme right end of the line.

Hence, the correct answer is "Option 1".

Question 19

PQRS is a trapezium in which QR || PS and PR = RS. If ∠PQR = 96° and ∠QPR = 34°, then what is the measure of ∠PRS?

  1. AOption (a)

    75°

  2. BOption (b)

    80°

  3. COption (c)

    70°

  4. DOption (d)

    65°

View answer & explanation

Correct answer

Answer: (b)B.

80°

Why this answer is correct

Shortcut Trick

In ΔPQR, sum of angles = 180° ⇒ ∠PRQ = 180° − (96° + 34°) = 50°.

Since QR || PS, alternate interior angles are equal ⇒ ∠SPR = ∠PRQ = 50°.

In ΔPRS, given PR = RS, so angles opposite to equal sides are equal ⇒ ∠PSR = ∠SPR = 50°.

Sum of angles in ΔPRS = 180° ⇒ ∠PRS = 180° − (50° + 50°) = 80°.

∴ The correct answer is 80°.

Alternate Method

Given: PQRS is a trapezium with QR || PS. PR = RS, ∠PQR = 96°, and ∠QPR = 34°.

Formula Used: Angle sum property of a triangle (Sum = 180°) and alternate interior angles property (when two lines are parallel).

Calculations:

⇒ In ΔPQR, ∠PQR + ∠QPR + ∠PRQ = 180°

⇒ 96° + 34° + ∠PRQ = 180°

⇒ 130° + ∠PRQ = 180°

⇒ ∠PRQ = 50°

⇒ Since QR || PS, ∠SPR = ∠PRQ (Alternate Interior Angles)

⇒ ∠SPR = 50°

⇒ In ΔPRS, given PR = RS, therefore ∠PSR = ∠SPR = 50° (Angles opposite to equal sides)

⇒ ∠PRS + ∠PSR + ∠SPR = 180°

⇒ ∠PRS + 50° + 50° = 180°

⇒ ∠PRS + 100° = 180°

⇒ ∠PRS = 80°

∴ The correct answer is 80°.

Additional Information

Isosceles Triangle Property

In a triangle, if two sides are equal, the angles opposite to those sides are also equal.

Parallel Lines & Transversals

When a transversal intersects two parallel lines, the alternate interior angles are always equal.

Angle Sum Property

The sum of all interior angles of any triangle is always 180°.

Question 20

The carbohydrates which are not used immediately are stored in the form of ________, which serves as the internal energy reserve to be used as and when required by the plant.

  1. AOption (a)

    cellulose

  2. BOption (b)

    starch

  3. COption (c)

    glucose

  4. DOption (d)

    glycogen

View answer & explanation

Correct answer

Answer: (b)B.

starch

Why this answer is correct

The correct answer is starch.

Key Points

  • Plants store carbohydrates in the form of starch, which is a polysaccharide.
  • Starch consists of two types of molecules: amylose (linear) and amylopectin (branched).
  • It serves as an internal energy reserve for plants, used during periods of low photosynthetic activity.
  • Starch is stored in plastids, such as chloroplasts and amyloplasts, within plant cells.
  • When energy is required, starch is broken down into glucose by enzymatic processes.

Additional Information

  • Cellulose
  • Cellulose is a structural polysaccharide and a major component of the plant cell wall.
  • It is composed of linear chains of glucose molecules linked by β-1,4-glycosidic bonds.
  • Unlike starch, cellulose cannot be digested by humans but can be broken down by some herbivores and microorganisms.
  • Glucose
  • Glucose is a simple monosaccharide sugar that serves as a primary energy source for cells.
  • It is directly used in cellular respiration to produce ATP.
  • Excess glucose can be converted into starch for storage in plants.
  • Glycogen
  • Glycogen is a storage form of glucose in animals and fungi, similar to starch in plants.
  • It is highly branched and stored mainly in the liver and muscle tissues.
  • Glycogen is broken down into glucose when energy is needed by the body.

Question 21

Which of the following tissues is present in stems, around vascular bundles, in the veins of leaves and the hard covering of seeds and nuts?

  1. AOption (a)

    Apical meristem

  2. BOption (b)

    Epidermis

  3. COption (c)

    Parenchyma

  4. DOption (d)

    Sclerenchyma

View answer & explanation

Correct answer

Answer: (d)D.

Sclerenchyma

Why this answer is correct

The correct answer is Sclerenchyma.

Key Points

  • Sclerenchyma is a type of supportive tissue in plants, characterized by thickened, lignified cell walls.
  • It is present in stems, around vascular bundles, in the veins of leaves, and the hard covering of seeds and nuts, providing structural support and strength.
  • Sclerenchyma cells are typically dead at maturity and provide rigidity and support to the plant.
  • This tissue is further divided into two types: fibers and sclereids, both contributing to the plant's mechanical strength.

Additional Information

  • Apical Meristem
  • It is a tissue found at the tips of roots and shoots, responsible for the primary growth of the plant.
  • Cells in the apical meristem are undifferentiated and actively divide to allow the plant to grow in length.
  • Epidermis
  • It is the outermost layer of cells covering the leaves, flowers, roots, and stems of plants.
  • The epidermis serves as a protective barrier against environmental stress and pathogens.
  • Parenchyma
  • This tissue is composed of living cells that are often involved in storage, photosynthesis, and tissue repair.
  • Parenchyma cells have thin cell walls and are found throughout the plant.
  • Collenchyma
  • It is a type of plant tissue that provides support to growing parts of the plant, such as young stems and leaves.
  • Collenchyma cells have unevenly thickened cell walls and are typically living at maturity.

Question 22

Refer to the following number and symbol series and answer the question that follows. Counting to be done from left to right only.

(Left) 2 9 + % 8 4 5 3 @ $ 7 & Ω # 1 * £ (Right)

How many such symbols are there, each of which is immediately preceded by another symbol and also immediately followed by a number$?

  1. AOption (a)

    2

  2. BOption (b)

    1

  3. COption (c)

    3

  4. DOption (d)

    4

View answer & explanation

Correct answer

Answer: (c)C.

3

Why this answer is correct

Given series: (Left) 2 9 + % 8 4 5 3 @ $ 7 & Ω # 1 * £ (Right)

According to the question,

Condition:  symbols - symbols -  number

 2 9 + % 8 4 5 3 @ $ 7 & Ω # 1 * £

Thus, there are 3 symbols which are preceded by a symbols and immediately followed by number.

Hence, "Option 3" is the correct answer.

Question 23

The smallest 3-digit natural number that is completely divisible by 8 and 12 is:

  1. AOption (a)

    124

  2. BOption (b)

    120

  3. COption (c)

    108

  4. DOption (d)

    144

View answer & explanation

Correct answer

Answer: (b)B.

120

Why this answer is correct

Shortcut Trick

Find the LCM of 8 and 12.

Multiples of 12: 12, 24, 36... Since 24 is divisible by 8, LCM(8, 12) = 24.

Smallest 3-digit number is 100. Divide 100 by 24: 100 ÷ 24 = 4 with remainder 4.

Next multiple of 24 after 100 is 24 × 5 = 120.

∴ The correct answer is 120.

Alternate Method

Given: Divisors are 8 and 12.

Formula Used: Required number = Smallest multiple of LCM(8, 12) that is ≥ 100.

⇒ Prime factorization of 8 = 2 × 2 × 2 = 23

⇒ Prime factorization of 12 = 2 × 2 × 3 = 22 × 3

⇒ LCM(8, 12) = 23 × 3 = 8 × 3 = 24

⇒ Smallest 3-digit number = 100

⇒ 100 ÷ 24: Quotient = 4, Remainder = 4

⇒ Smallest 3-digit multiple = 24 × (4 + 1) = 24 × 5 = 120

∴ The correct answer is 120.

Additional Information

LCM (Least Common Multiple)

The smallest positive integer that is divisible by both a and b. It is the product of the highest powers of all prime factors involved.

Divisibility Rule of 8

A number is divisible by 8 if its last three digits are divisible by 8. For 3-digit numbers, use direct division.

Divisibility Rule of 12

A number is divisible by 12 if it is simultaneously divisible by both 3 (sum of digits rule) and 4 (last two digits rule).

Question 24

An amount is distributed among A, B and C in the ratio of 5 : 7 : 15. If B's share is ₹1,400 out of the total amount, then the total amount is:

  1. AOption (a)

    ​₹8,100

  2. BOption (b)

    ₹2,700

  3. COption (c)

    ₹5,400

  4. DOption (d)

    ​₹4,200

View answer & explanation

Correct answer

Answer: (c)C.

₹5,400

Why this answer is correct

Shortcut Trick

Ratio of shares A : B : C = 5 : 7 : 15.

Given B's share (7 units) = ₹1,400.

Total units = 5 + 7 + 15 = 27 units.

Total amount = (1,400 ÷ 7) × 27 = 200 × 27 = ₹5,400.

∴ The correct answer is ₹5,400.

Alternate Method

Given:

Ratio of A, B, and C = 5 : 7 : 15

B's share = ₹1,400

Calculations:

⇒ Let the shares be 5x, 7x, and 15x.

⇒ 7x = 1,400

⇒ x = 1,400 ÷ 7 = 200

⇒ Total amount = 5x + 7x + 15x = 27x

⇒ Total amount = 27 × 200 = ₹5,400

∴ The correct answer is ₹5,400.

Additional Information

Concept of Ratio Distribution

To find an individual's share, use the formula: (Individual Ratio ÷ Sum of Ratios) × Total Amount.

Compound Ratio

If ratios are given as A:B and B:C, the combined ratio A:B:C is calculated by equating the common term B.

Direct Proportion in Sharing

The actual value of each share is directly proportional to its respective ratio part when the total amount is constant.

Question 25

What is the primary difference between the particles of a solid and those of a gas?

  1. AOption (a)

    Solid particles move more freely than gas particles.

  2. BOption (b)

    Solid particles are more closely packed than gas particles

  3. COption (c)

    Solid particles have more energy than gas particles.

  4. DOption (d)

    Solid particles are made of different elements than gas particles.

View answer & explanation

Correct answer

Answer: (b)B.

Solid particles are more closely packed than gas particles

Why this answer is correct

The correct answer is Solid particles are more closely packed than gas particles.

Key Points

  • Solid particles are more closely packed than gas particles, leading to a fixed shape and volume for solids.
  • In solids, the particles are in a fixed, orderly arrangement, resulting in a rigid structure.
  • Gas particles are spread out and move freely, leading to no fixed shape or volume for gases.
  • The close packing of solid particles results in higher density compared to gases.
  • Solids have lower kinetic energy in their particles compared to gases, where particles move rapidly and randomly.

Additional Information

  • States of Matter:
  • Matter exists primarily in three states: solid, liquid, and gas.
  • Each state is characterized by different arrangements and movements of its particles.
  • Kinetic Theory of Gases:
  • This theory explains the behavior of gas particles, stating that they are in constant, random motion.
  • The temperature of a gas is a measure of the average kinetic energy of its particles.
  • Density and Volume:
  • Density is the mass per unit volume of a substance.
  • Solids generally have higher density than gases due to closer particle packing.
  • Intermolecular Forces:
  • These are forces that hold particles together in a solid or liquid.
  • In solids, intermolecular forces are strong, giving solids a definite shape and volume.
  • In gases, these forces are negligible, allowing particles to move independently.

Question 26

What will come in the place of "?" in the following equation, if '-' and '×' are interchanged and '+' and '÷ ' are interchanged?

23 × 13 - 7 ÷ 14 + 7 = ?

  1. AOption (a)

    -66

  2. BOption (b)

    -56

  3. COption (c)

    -92

  4. DOption (d)

    -76

View answer & explanation

Correct answer

Answer: (a)A.

-66

Why this answer is correct

Given: 23 × 13 - 7 ÷ 14 + 7 = ?

According to the question,  '-' and '×' are interchanged and '+' and '+' are interchanged

23 × 13 - 7 ÷ 14 + 7 = ?

⇒ 23 - 13 × 7 + 14 ÷ 7 = ?

​⇒ 23 - 91 + 2

​⇒ 25 - 91 = -66

Hence, the correct answer is "Option 1".

Question 27

Select the correct equation(s) that relate(s) the final and initial velocity of a freely falling object with respect to time.

(A) s = ut +2at2

(B) v = u + 12\frac{1}{2}at

(C) (v - u) = at

  1. AOption (a)

    (B) and (C)

  2. BOption (b)

    Only (C)

  3. COption (c)

    (A) and (B)

  4. DOption (d)

    Only (A)

View answer & explanation

Correct answer

Answer: (b)B.

Only (C)

Why this answer is correct

The correct answer is Only (C).

Key Points

  • Equation (C), (v−u)=at(v-u)=at, is derived from the basic definition of acceleration: acceleration (a) is the rate of change of velocity with time (t).
  • This equation applies directly to uniformly accelerated motion, such as that of a freely falling object under gravity.
  • It relates the final velocity (v) of an object to its initial velocity (u), acceleration (a), and the time of travel (t).
  • Equations (A) and (B) are not correctly written or applicable in the context of a freely falling object.

Additional Information

  • Equations of Motion:
  • There are three primary equations of motion that describe the behavior of objects in uniformly accelerated linear motion:
  • v=u+atv=u+at
  • s=ut+12at2s=ut+\frac{1}{2}at^2
  • v2=u2+2asv^2=u^2+2as
  • These equations are essential in classical mechanics and are used to predict future motion based on current conditions.
  • Uniform Acceleration:
  • Uniform acceleration refers to a constant acceleration, meaning the velocity of the object changes at a constant rate.
  • In the case of free fall, the acceleration due to gravity (g) is approximately 9.81 m/s² near the Earth's surface.
  • Free Fall:
  • Free fall is the motion of an object under the influence of gravitational force only.
  • During free fall, the only force acting on the object is gravity, leading to a uniform acceleration downwards.
  • Initial and Final Velocity:
  • Initial velocity (u) is the velocity of the object before it starts accelerating.
  • Final velocity (v) is the velocity of the object after it has been accelerating for a certain period of time.

Question 28

Which hormone is present in greater concentration in areas of rapid cell division and promote cell division?

  1. AOption (a)

    Cytokinin

  2. BOption (b)

    Abscisic acid

  3. COption (c)

    Gibberellins

  4. DOption (d)

    Auxins

View answer & explanation

Correct answer

Answer: (a)A.

Cytokinin

Why this answer is correct

The correct answer is Cytokinin.

Key Points

  • Cytokinins are a class of plant hormones that promote cell division, or cytokinesis, in plant roots and shoots.
  • They are present in higher concentrations in areas of rapid cell division such as growing tissues and meristems.
  • Cytokinins work in conjunction with auxins to stimulate cell division, elongation, and differentiation.
  • These hormones play a crucial role in various plant growth processes, including leaf expansion, chloroplast development, and delay of senescence (aging).

Additional Information

  • Abscisic Acid (ABA)
  • It is a plant hormone that plays a major role in plant stress responses, including stomatal closure during drought stress.
  • ABA inhibits cell division and promotes leaf and fruit abscission (dropping).
  • Gibberellins
  • These are plant hormones that promote stem elongation, seed germination, and flowering.
  • They work by breaking seed dormancy and aiding in the mobilization of nutrients during seed germination.
  • Auxins
  • Auxins are crucial for the regulation of plant growth and development.
  • They are primarily involved in cell elongation, root initiation, and response to light (phototropism) and gravity (gravitropism).
  • Plant Meristems
  • Meristems are regions in plants where active cell division occurs, leading to the growth of new tissues.
  • There are two main types of meristems: apical meristems (found at the tips of roots and shoots) and lateral meristems (responsible for secondary growth).

Question 29

Based on the English alphabetical order, three of the following four letter-clusters are alike in a certain way and thus form a group. Which letter-cluster does not belong to that group?

(Note: The odd one out is not based on the number of consonants/vowels or their position in the letter-cluster.)

  1. AOption (a)

    FAW

  2. BOption (b)

    XSN

  3. COption (c)

    EZU

  4. DOption (d)

    WRM

View answer & explanation

Correct answer

Answer: (a)A.

FAW

Why this answer is correct

The logic followed here is:

Option 1) FAW

Option 2) XSN

Option 3) EZU

Option 4) WRM

Hence, the correct answer is "Option 1

Question 30

According to the Bohr's model, what is the maximum number of electrons for the second energy level?

  1. AOption (a)

    6

  2. BOption (b)

    4

  3. COption (c)

    8

  4. DOption (d)

    2

View answer & explanation

Correct answer

Answer: (c)C.

8

Why this answer is correct

The correct answer is 8.

Key Points

  • According to the Bohr model, the second energy level can hold a maximum of 8 electrons.
  • Electrons in an atom are arranged in energy levels or shells, which are denoted by the principal quantum number (n).
  • The formula to determine the maximum number of electrons in a shell is given by 2n2, where n is the principal quantum number.
  • For the second energy level (n=2), the maximum number of electrons is calculated as 2(2)2 = 8.
  • This concept is foundational to understanding the electron configuration of atoms and their chemical properties.

Additional Information

  • Principal Quantum Number (n)
  • It denotes the energy level of an electron within an atom.
  • The value of n determines the size and energy of the orbital.
  • Higher values of n correspond to higher energy levels and larger orbitals.
  • Bohr Model
  • Proposed by Niels Bohr in 1913, it describes electrons orbiting the nucleus in fixed energy levels.
  • Electrons can jump between energy levels by absorbing or emitting specific amounts of energy.
  • The model helped explain the spectral lines of hydrogen.
  • Electron Configuration
  • It describes the distribution of electrons in the different energy levels or orbitals of an atom.
  • It follows a specific order based on the Aufbau principle, Pauli exclusion principle, and Hund's rule.
  • Electron configuration helps predict chemical behavior and bonding.
  • Aufbau Principle
  • It states that electrons fill lower energy orbitals first before moving to higher energy orbitals.
  • This principle guides the order in which atomic orbitals are filled.

Question 31

A tap can fill a tank in 6 hours. After half the tank is filled, three more similar taps are opened. What is the total time taken to fill the tank completely?

  1. AOption (a)

    4 hours 15 min

  2. BOption (b)

    4 hours

  3. COption (c)

    3 hours 45 min

  4. DOption (d)

    3 hours 15 min

View answer & explanation

Correct answer

Answer: (c)C.

3 hours 45 min

Why this answer is correct

Shortcut Trick

Time taken to fill half the tank by 1 tap = 6 ÷ 2 = 3 hours.

The remaining half of the tank is filled by 4 identical taps (1 original + 3 new).

Time taken by 4 taps to fill the remaining half = Time taken by 1 tap ÷ 4 = 3 ÷ 4 hours = 45 minutes.

Total time = 3 hours + 45 minutes = 3 hours 45 min.

∴ The correct answer is 3 hours 45 min.

Alternate Method

TapHoursTotal WorkEfficiency
1 Tap661
4 Taps1.54

⇒ Let the total capacity of the tank be the LCM = 6 units.

⇒ Efficiency of 1 tap = 1 unit/hour.

⇒ Time taken by 1 tap to fill half the tank (3 units) = 3 ÷ 1 = 3 hours.

⇒ Remaining work to be done = 6 − 3 = 3 units.

⇒ Now, 3 more similar taps are opened. Total taps operating = 1 + 3 = 4 taps.

⇒ Combined efficiency of 4 taps = 4 × 1 = 4 units/hour.

⇒ Time taken to complete the remaining work = Remaining work ÷ Efficiency = 3 ÷ 4 hours.

⇒ Converting into minutes = (3 ÷ 4) × 60 = 45 minutes.

⇒ Total time taken to fill the tank completely = 3 hours + 45 minutes = 3 hours 45 min.

∴ The correct answer is 3 hours 45 min.

Additional Information

Pipes & Cisterns Net Work

If pipe A fills a tank in x hours and pipe B fills it in y hours, their combined 1 hour work is (1/x + 1/y).

Efficiency of Multiple Identical Sources

When n identical taps are opened simultaneously, their combined efficiency becomes n times the efficiency of a single tap, effectively reducing the time required to 1/n.

Work Equivalence

Total Work = Number of identical workers (or taps) × Time taken × Efficiency. This is a direct application of the unitary method in Time & Work.

Question 32

In which of the following states was the 4th Asmita Khelo India National Judo League/Ranking Judo Tournament 2024-25 held?

  1. AOption (a)

    Karnataka

  2. BOption (b)

    Madhya Pradesh

  3. COption (c)

    Jharkhand

  4. DOption (d)

    Kerala

View answer & explanation

Correct answer

Answer: (d)D.

Kerala

Why this answer is correct

The correct answer is Kerala.

Key Points

  • The 4th Asmita Khelo India National Judo League/Ranking Judo Tournament 2024-25 was held in Kerala.
  • This tournament is part of the Khelo India initiative, which aims to promote sports at the grassroots level across India.
  • The event witnessed participation from various states, showcasing the best judo talents in the country.
  • It serves as a platform for young athletes to gain national exposure and compete at a high level.
  • The tournament is organized annually under the auspices of the Ministry of Youth Affairs and Sports, Government of India.

Additional Information

  • Khelo India Programme
  • Launched by the Government of India in 2018 to revive the sports culture in India at the grassroots level.
  • Aims to encourage mass participation and excellence in sports.
  • Focuses on building sports infrastructure and providing financial assistance to promising athletes.
  • Includes initiatives like Khelo India Youth Games, Khelo India University Games, and the development of sports academies.
  • Judo
  • A modern martial art, combat, and Olympic sport created in Japan in 1882 by Jigoro Kano.
  • The objective is to throw or takedown the opponent to the ground, immobilize them, or force them into submission.
  • Judo became an official Olympic sport for men in 1964 and for women in 1992.
  • It emphasizes the principles of maximum efficiency and mutual welfare and benefit.

Question 33

What historic achievement did Manu Bhaker accomplish at the 2024 Paris Olympics? 

  1. AOption (a)

    First Indian to win an Olympic medal in shooting

  2. BOption (b)

    First athlete to win medals in both individual and team events

  3. COption (c)

    First Indian female shooter to win an Olympic gold

  4. DOption (d)

    First athlete of independent India to win two Olympic medals in a single edition

View answer & explanation

Correct answer

Answer: (d)D.

First athlete of independent India to win two Olympic medals in a single edition

Why this answer is correct

The correct answer is First athlete of independent India to win two Olympic medals in a single edition.

Key Points

  • Manu Bhaker became the first athlete of independent India to win two Olympic medals in a single edition at the 2024 Paris Olympics.
  • She achieved this historic feat by securing medals in both the individual women's 10m air pistol event and the mixed team 10m air pistol event.
  • This landmark achievement marks a significant milestone in India's Olympic history, showcasing her exceptional talent and dedication.
  • Manu Bhaker's performance at the 2024 Paris Olympics has inspired many young athletes in the country to pursue their dreams in sports.

Additional Information

  • Olympic Shooting Events:
  • Shooting events in the Olympics are divided into rifle, pistol, and shotgun categories.
  • Competitors aim to hit targets with precision to score points, with the highest scores winning medals.
  • Events are held for both men and women, individually and in teams.
  • 10m Air Pistol:
  • This is a precision shooting event where competitors shoot at a target 10 meters away.
  • It involves shooting 60 shots within a time limit, and the highest total score determines the winner.

Question 34

Refer to the given number and symbol series and answer the question that follows. Counting to be done from left to right only.

(Left) 2 % 8 4 5 3 @ # 1 * $ 7 & 9 + Ω 6 £ (Right)

How many such numbers are there, each of which is immediately preceded by another number and also immediately followed by a symbol$?

  1. AOption (a)

    1

  2. BOption (b)

    2

  3. COption (c)

    0

  4. DOption (d)

    3

View answer & explanation

Correct answer

Answer: (a)A.

1

Why this answer is correct

Given Series: 2 % 8 4 5 3 @ # 1 * $ 7 & 9 + Ω 6 £ 

Condition: number - number - symbol

2 % 8 4 5 3 @ # 1 * $ 7 & 9 + Ω 6 £ 

Thus, here only 1 follow the condition.

Hence, the correct answer is "Option 1".

Question 35

Among all the seven-coloured lights, which colour deviates the most after falling on a prism?

  1. AOption (a)

    Indigo

  2. BOption (b)

    Yellow

  3. COption (c)

    Red

  4. DOption (d)

    Violet

View answer & explanation

Correct answer

Answer: (d)D.

Violet

Why this answer is correct

The correct answer is Violet.

Key Points

  • When white light passes through a prism, it gets dispersed into its constituent colours, forming a spectrum.
  • The deviation of light is due to the phenomenon of refraction, which occurs as light changes speed when passing through different media.
  • Violet light deviates the most because it has the shortest wavelength among the visible spectrum.
  • Due to its shorter wavelength, violet light is refracted at a greater angle compared to other colours.
  • This increased deviation is why violet appears at the bottom of the spectrum when white light is dispersed by a prism.

Additional Information

  • Dispersion of Light
  • Dispersion occurs when light separates into its different colour components due to varying degrees of refraction for different wavelengths.
  • This phenomenon is often observed with a prism or in natural occurrences like rainbows.
  • Refraction
  • Refraction is the bending of light as it passes from one medium to another with a different density.
  • The amount of bending depends on the indices of refraction of the two media and the angle of incidence.
  • Spectrum of Visible Light
  • The visible spectrum consists of colours red, orange, yellow, green, blue, indigo, and violet (ROYGBIV).
  • These colours correspond to wavelengths roughly between 400 nm (violet) and 700 nm (red).

Question 36

Simplify the given expression.

3 + 6 × (5 + 4) ÷ 3 - 7

  1. AOption (a)

    11

  2. BOption (b)

    15

  3. COption (c)

    14

  4. DOption (d)

    16

View answer & explanation

Correct answer

Answer: (c)C.

14

Why this answer is correct

Given:

Expression = 3 + 6 × (5 + 4) ÷ 3 − 7

Formula used:

BODMAS Rule (Brackets, Of, Division, Multiplication, Addition, Subtraction)

Calculations:

3 + 6 × (5 + 4) ÷ 3 − 7

⇒ 3 + 6 × 9 ÷ 3 − 7

⇒ 3 + 6 × 3 − 7

⇒ 3 + 18 − 7

⇒ 21 − 7

⇒ 14

∴ The correct answer is option (3).

Question 37

While subtracting –2 from −310\frac{-3}{10}, the resultant value is:

  1. AOption (a)

    1351 \frac{3}{5}

  2. BOption (b)

    13101 \frac{3}{10}

  3. COption (c)

    1451 \frac{4}{5}

  4. DOption (d)

    17101 \frac{7}{10}

View answer & explanation

Correct answer

Answer: (d)D.

17101 \frac{7}{10}

Why this answer is correct

Given:

Number to be subtracted from = −3/10

Number to be subtracted = −2

Formula used:

Result = (Value 1) − (Value 2)

Calculations:

Result = (−3/10) − (−2)

⇒ Result = −3/10 + 2

⇒ Result = (−3 + 20)/10

⇒ Result = 17/10

⇒ Result = 1 7/10

∴ The correct answer is option (4).

Question 38

Which of the following options should come in place of the question mark (?) in the given series to make it logically complete?

859, 768, 677, 586, 495, ?

  1. AOption (a)

    404

  2. BOption (b)

    426

  3. COption (c)

    462

  4. DOption (d)

    388

View answer & explanation

Correct answer

Answer: (a)A.

404

Why this answer is correct

The logic followed here is:

Logic: The difference of number is 91.

Hence, the correct answer is "Option 1".

Question 39

Study the following chart and answer the question that follows.

What is the total exports by Company X and Y in months of January and March?

  1. AOption (a)

    385 crore

  2. BOption (b)

    375 crore

  3. COption (c)

    380 crore

  4. DOption (d)

    365 crore

View answer & explanation

Correct answer

Answer: (c)C.

380 crore

Why this answer is correct

Given:

Exports by Company X in January = 95 crores

Exports by Company X in March = 85 crores

Exports by Company Y in January = 100 crores

Exports by Company Y in March = 100 crores

Formula used:

Total exports = Exports by Company X (Jan) + Exports by Company X (Mar) + Exports by Company Y (Jan) + Exports by Company Y (Mar)

Calculation:

⇒ Total exports = 95 + 85 + 100 + 100

⇒ Total exports = 380 crores

∴ The total exports by Company X and Y in January and March is 380 crores.

Question 40

If a train travelling with a velocity of 20 m/s undergoes a uniform acceleration of 4 m/s2, what is the value of its velocity in 5 seconds?

  1. AOption (a)

    60 m/s

  2. BOption (b)

    16 m/s

  3. COption (c)

    40 m/s

  4. DOption (d)

    80 m/s

View answer & explanation

Correct answer

Answer: (c)C.

40 m/s

Why this answer is correct

The correct answer is 40 m/s.

Key Points

  • Formula: v = u + at
  • Given: initial velocity (u) = 20 m/s, acceleration (a) = 4 m/s², and time (t) = 5 seconds.
  • Substituting the values into the formula: v = 20 m/s + (4 m/s² * 5 s).
  • The calculation yields: v = 20 m/s + 20 m/s = 40 m/s.
  • Thus, the final velocity of the train after 5 seconds is 40 m/s.

Additional Information

  • Uniform Acceleration:
  • It occurs when an object's velocity changes at a constant rate.
  • The equations of motion for uniformly accelerated motion are key tools in physics to predict the future position and velocity of an object.
  • Equations of Motion:
  • There are three main equations used to describe motion under uniform acceleration:
  • v=u+atv=u+at
  • s=ut+12at2s=ut+\frac{1}{2}at^2
  • v2=u2+2asv^2=u^2+2as
  • These equations are essential for solving various problems in kinematics.
  • Velocity:
  • Velocity is a vector quantity that refers to the rate at which an object changes its position.
  • It has both magnitude and direction, distinguishing it from speed, which is a scalar quantity.
  • Acceleration:
  • Acceleration is the rate of change of velocity of an object with respect to time.
  • It is a vector quantity and can be caused by changes in speed, direction, or both.

Question 41

Why did the Government of India remove the 'monument of national importance' status from the statue of John Nicholson?

  1. AOption (a)

    The statue was found to be historically inaccurate.

  2. BOption (b)

    It was considered irrelevant to India's independence struggle. 

  3. COption (c)

    It was linked to British colonial legacy. 

  4. DOption (d)

    The statue was in a deteriorating condition.

View answer & explanation

Correct answer

Answer: (c)C.

It was linked to British colonial legacy. 

Why this answer is correct

The correct answer is It was linked to British colonial legacy..

Key Points

  • The statue of John Nicholson was linked to the British colonial rule in India.
  • John Nicholson was a British Army officer known for his role during the Indian Rebellion of 1857.
  • The government's move aligns with the broader effort to address and rectify colonial-era symbols in public spaces.
  • Removing such statues is part of the decolonization process and the reassertion of Indian historical and cultural identity.

Additional Information

  • John Nicholson
  • He was a British officer known for his role in suppressing the Indian Rebellion of 1857.
  • He is often remembered for his brutal methods against Indian rebels.
  • His actions and legacy are controversial, seen as oppressive by many in India.
  • Indian Rebellion of 1857
  • Also known as the First War of Indian Independence.
  • It marked a significant resistance against British rule in India.
  • The revolt led to the dissolution of the East India Company and the reorganization of British governance in India.
  • Decolonization
  • The process of decolonization involves the removal of colonial symbols and the reassertion of indigenous culture and history.
  • It is aimed at addressing the historical injustices and colonial narratives.
  • Many countries have undertaken similar initiatives to reclaim their cultural heritage.
  • Government's Efforts
  • The Indian government has been actively removing colonial-era statues and symbols.
  • It is part of a broader initiative to promote national pride and cultural heritage.
  • Such efforts include renaming streets and institutions that bear colonial names.

Question 42

Starting from rest, Raju attains a velocity of 24 m/s in a minute with his bicycle. The acceleration of the bicycle is:

  1. AOption (a)

    0 m/s2

  2. BOption (b)

    0.2 m/s2

  3. COption (c)

    0.4 m/s2

  4. DOption (d)

    0.6 m/s2

View answer & explanation

Correct answer

Answer: (c)C.

0.4 m/s2

Why this answer is correct

The correct answer is 0.4 m/s².

Key Points

  • The initial velocity (u) of Raju's bicycle is 0 m/s as he starts from rest.
  • The final velocity (v) reached by Raju's bicycle is 24 m/s.
  • The time (t) taken to reach this velocity is 60 seconds (1 minute).
  • Acceleration (a) can be calculated using the formula: a=(v−u)ta=\frac{(v-u)}{t}
  • Substituting the values: a = (24 m/s - 0 m/s) / 60 s = 0.4 m/s².

Additional Information

  • Acceleration
  • Acceleration is the rate of change of velocity of an object with respect to time.
  • It is a vector quantity, which means it has both magnitude and direction.
  • Common units of acceleration are meters per second squared (m/s²).
  • Velocity
  • Velocity is the speed of an object in a given direction.
  • It is also a vector quantity.
  • The SI unit of velocity is meters per second (m/s).
  • Distance and Displacement
  • Distance is the total path covered by an object, irrespective of direction.
  • Displacement is the shortest distance from the initial to the final position of an object in a straight line.
  • Both are measured in meters (m).
  • Kinematic Equations
  • Kinematic equations relate the motion of an object to time, velocity, acceleration, and displacement.
  • They are used to solve problems involving linear motion with constant acceleration.
  • Examples include: 
  • v=u+atv=u+at
  • s=ut+12at2s=ut+\frac{1}{2}at^2
  • v2=u2+2asv^2=u^2+2as

Question 43

Select the triad which follows the same pattern as that followed by the two triads given below. Both triads follow the same pattern.

TX-VS-WY

UY-WT-XZ

  1. AOption (a)

    FJ-HE-IL

  2. BOption (b)

    OS-QN-RT

  3. COption (c)

    LP-NK-OR

  4. DOption (d)

    IM-KH-LO

View answer & explanation

Correct answer

Answer: (b)B.

OS-QN-RT

Why this answer is correct

The logic followed here is:

For, TX-VS-WY

For, UY-WT-XZ

Let's check options one by one:

Option 1) FJ-HE-IL

Option 2) OS-QN-RT

Here, it follow the pattern.

Option 3) LP-NK-OR

Option 4) IM-KH-LO

Hence, the correct answer is "Option 2".

Question 44

The term _______ refers to the densely packed kidney filtration unit.

  1. AOption (a)

    Glomerulus

  2. BOption (b)

    Nephron

  3. COption (c)

    Capillary

  4. DOption (d)

    Neurone

View answer & explanation

Correct answer

Answer: (a)A.

Glomerulus

Why this answer is correct

The correct answer is Glomerulus.

Key Points

  • The glomerulus is a network of capillaries located at the beginning of a nephron in the kidney.
  • It is involved in the filtration of blood to form urine.
  • The glomerulus allows the passage of water, ions, and small molecules from the blood into the Bowman's capsule.
  • It retains large molecules like proteins and blood cells within the bloodstream.

Additional Information

  • Nephron
  • The nephron is the functional unit of the kidney responsible for urine formation.
  • Each nephron includes a glomerulus and a renal tubule.
  • There are approximately 1 million nephrons in each human kidney.
  • The nephron performs essential functions like filtration, reabsorption, secretion, and excretion.
  • Bowman's Capsule
  • The Bowman's capsule is a cup-like sac that encases the glomerulus.
  • It collects the filtrate that emerges from the glomerulus.
  • This structure initiates the process of filtering blood to form urine.
  • Renal Tubule
  • The renal tubule processes the filtrate from the Bowman's capsule.
  • It includes segments like the proximal convoluted tubule, loop of Henle, distal convoluted tubule, and collecting duct.
  • Each segment plays a specific role in reabsorbing water and solutes or secreting substances into the filtrate.
  • Filtration Barrier
  • The filtration barrier in the glomerulus consists of three layers: endothelial cells, basement membrane, and podocytes.
  • It selectively allows the passage of small molecules while preventing large molecules like proteins from passing through.
  • This barrier is crucial for maintaining the composition of blood and filtrate.

Question 45

In a certain code language, 'WIFE' is coded as '1852' and 'FIRE' is coded as '7258'. What is the code for 'R' in the given code language?

  1. AOption (a)

    8

  2. BOption (b)

    2

  3. COption (c)

    5

  4. DOption (d)

    7

View answer & explanation

Correct answer

Answer: (d)D.

7

Why this answer is correct

The logic followed here is:

The code for "R" is "7".

Hence, the correct answer is "Option 4".

Question 46

An organism simply splits into two equal halves during cell division. What is it known as?

  1. AOption (a)

    Regeneration

  2. BOption (b)

    Budding

  3. COption (c)

    Binary fission

  4. DOption (d)

    Spore formation

View answer & explanation

Correct answer

Answer: (c)C.

Binary fission

Why this answer is correct

The correct answer is Binary fission.

Key Points

  • Binary fission is a type of asexual reproduction common among prokaryotes such as bacteria.
  • In binary fission, an organism duplicates its genetic material and then divides into two equal-sized daughter cells.
  • This process ensures that each daughter cell receives a copy of the parent organism's genetic material.
  • Binary fission is efficient and allows for rapid population growth, especially in favorable environments.

Additional Information

  • Regeneration
  • Regeneration is the process by which certain organisms can regrow lost or damaged parts of their body.
  • Examples include the regrowth of limbs in starfish or tails in lizards.
  • This is different from binary fission as it involves repairing or replacing damaged structures rather than creating new organisms.
  • Budding
  • Budding is another form of asexual reproduction where a new organism develops from an outgrowth or bud due to cell division at one particular site.
  • It is commonly observed in yeast and some invertebrates like hydra.
  • Unlike binary fission, budding results in the formation of a new organism while the parent organism remains.
  • Spore formation
  • Spore formation is a method of asexual reproduction that involves the formation of spores by the parent organism.
  • These spores are typically resistant to extreme conditions and can remain dormant for long periods.
  • When conditions become favorable, spores germinate to form new organisms.
  • This is a common reproductive strategy among fungi and some bacteria.

Question 47

Many nerve fibres are bound together by which tissue and make up a nerve?

  1. AOption (a)

    Vascular tissue

  2. BOption (b)

    Meristematic tissue

  3. COption (c)

    Connective tissue

  4. DOption (d)

    Epithelial tissue

View answer & explanation

Correct answer

Answer: (c)C.

Connective tissue

Why this answer is correct

The correct answer is Connective tissue.

Key Points

  • Connective tissue is one of the four main types of tissue in the body, the others being epithelial, muscle, and nervous tissues.
  • Nerve fibers are bound together by connective tissue, which provides structural support and protection.
  • In nerves, connective tissue layers are classified into endoneurium, perineurium, and epineurium.
  • The endoneurium surrounds individual nerve fibers, the perineurium surrounds bundles of nerve fibers (fascicles), and the epineurium surrounds the entire nerve.
  • This hierarchical organization of connective tissue ensures that nerves are protected and can function effectively.

Additional Information

  • Types of Connective Tissue:
  • Loose connective tissue: Includes areolar, adipose, and reticular tissues.
  • Dense connective tissue: Includes dense regular, dense irregular, and elastic tissues.
  • Functions of Connective Tissue:
  • Provides structural support to organs and tissues.
  • Protects and insulates internal organs.
  • Stores energy reserves, particularly in the form of fat.
  • Transports substances within the body, particularly through blood, which is a type of connective tissue.
  • Nerve Structure:
  • Nerves are composed of neurons, the fundamental units of the nervous system that transmit signals.
  • Neurons are surrounded by myelin sheaths, which are produced by Schwann cells in the peripheral nervous system.
  • Connective Tissue Disorders:
  • Examples include Ehlers-Danlos syndrome, Marfan syndrome, and systemic lupus erythematosus.
  • These disorders can affect the integrity and function of connective tissues, leading to a variety of symptoms and complications.

Question 48

In a certain code language, ‘over the top' is written as 'ak ot yh' and 'the rock is 'is coded as 'ot gb tk '. How is 'the' coded in the given language?

  1. AOption (a)

    mr

  2. BOption (b)

    ot

  3. COption (c)

    Sy

  4. DOption (d)

    ql

View answer & explanation

Correct answer

Answer: (b)B.

ot

Why this answer is correct

The logic followed here is:

The code for "the" is "ot".

Hence, the correct answer is "Option 2".

Question 49

Who took the oath as the new Chief Minister of Haryana in the Assembly Election 2024?

  1. AOption (a)

    Shri Manohar Lal Khattar

  2. BOption (b)

    Shri Nayab Singh Saini

  3. COption (c)

    Shri Dushyant Chautala

  4. DOption (d)

    Shri Om Prakash Chautala

View answer & explanation

Correct answer

Answer: (b)B.

Shri Nayab Singh Saini

Why this answer is correct

The correct answer is Shri Nayab Singh Saini.

Key Points

  • Shri Nayab Singh Saini took the oath as the new Chief Minister of Haryana after the Assembly Election 2024.
  • He succeeded Shri Manohar Lal Khattar, who served as the Chief Minister of Haryana from 2014 to 2024.
  • Shri Nayab Singh Saini is known for his work in the Haryana Legislative Assembly and his efforts towards the development of the state.
  • His election as the Chief Minister marks a significant change in the political landscape of Haryana.

Additional Information

  • Haryana Legislative Assembly
  • The Haryana Legislative Assembly, also known as the Haryana Vidhan Sabha, is the unicameral state legislature of Haryana.
  • It consists of 90 members who are elected every five years.
  • The assembly meets at Vidhan Bhavan in Chandigarh, the capital of Haryana.
  • Chief Minister of Haryana
  • The Chief Minister of Haryana is the head of the government of the Indian state of Haryana.
  • The Chief Minister is appointed by the Governor of Haryana.
  • The term of the Chief Minister is for five years, subject to no term limits.
  • Political Landscape of Haryana
  • Haryana has a multi-party political system with major parties including the Bharatiya Janata Party (BJP), Indian National Congress (INC), and the Jannayak Janata Party (JJP).
  • The state has seen significant political shifts over the years, with various parties forming the government at different times.
  • Development Initiatives in Haryana
  • Haryana has been focusing on various development initiatives across sectors such as agriculture, education, and infrastructure.
  • Recent governments have emphasized the importance of industrial development and improving the ease of doing business in the state.

Question 50

Which of the following is/are the example/s of double displacement reaction?

(1) C(s) + O2(g) → CO2(g)

(2) Na2SO4(aq) + BaCl2(aq) → BaSO4 (s) + 2NaCl(aq)

(3) Pb(s) + CuCl2(aq) → PbCl2(aq) + Cu(s)

(4) CaCO3(s) → CaO(s) + CO2(g)

  1. AOption (a)

    Only 2

  2. BOption (b)

    2 and 3 only

  3. COption (c)

    1, 2 and 3 only

  4. DOption (d)

    1 and 4 only

View answer & explanation

Correct answer

Answer: (a)A.

Only 2

Why this answer is correct

The correct answer is Only 2.

Key Points

  • Double displacement reactions involve the exchange of ions between two compounds to form new compounds.
  • In the reaction Na2SO4(aq) + BaCl2(aq) → BaSO4(s) + 2NaCl(aq), the sulfate (SO42-) and chloride (Cl-) ions are displaced and form new products.
  • This type of reaction typically produces a precipitate, a gas, or water.
  • Double displacement reactions are also known as metathesis reactions.

Additional Information

  • Single Displacement Reactions
  • Involve one element being replaced by another in a compound.
  • Example: Pb(s) + CuCl2(aq) → PbCl2(aq) + Cu(s).
  • Combination Reactions
  • Two or more substances combine to form a single product.
  • Example: C(s) + O2(g) → CO2(g).
  • Decomposition Reactions
  • A single compound breaks down into two or more simpler substances.
  • Example: CaCO3(s) → CaO(s) + CO2(g).
  • Precipitation Reactions
  • A type of double displacement reaction where an insoluble solid (precipitate) forms.
  • Example: Na2SO4(aq) + BaCl2(aq) → BaSO4(s) + 2NaCl(aq).

Question 51

Simplify the given expression.

5 + 9 - 9 ÷ 3 × 4

  1. AOption (a)

    6

  2. BOption (b)

    5

  3. COption (c)

    2

  4. DOption (d)

    3

View answer & explanation

Correct answer

Answer: (c)C.

2

Why this answer is correct

Given:

Expression: 5 + 9 − 9 ÷ 3 × 4

Formula used:

The BODMAS/VBODMAS rule (Brackets, Orders, Division, Multiplication, Addition, Subtraction) defines the order of operations.

Calculations:

Step 1: Perform Division (9 ÷ 3)

⇒ 5 + 9 − 3 × 4

Step 2: Perform Multiplication (3 × 4)

⇒ 5 + 9 − 12

Step 3: Perform Addition (5 + 9)

⇒ 14 − 12

Step 4: Perform Subtraction (14 − 12)

⇒ 2

∴ The correct answer is option (3).

Question 52

The average of two numbers is M. If one number is N, then the other number is:

  1. AOption (a)

    2N

  2. BOption (b)

    2M

  3. COption (c)

    M-N

  4. DOption (d)

    2M-N

View answer & explanation

Correct answer

Answer: (d)D.

2M-N

Why this answer is correct

Shortcut Trick

Sum of observations = Average × Number of observations.

Total sum of two numbers = M × 2 = 2M.

Other number = Total Sum − First Number = 2M − N.

∴ The correct answer is 2M-N.

Alternate Method

Given:

Average of two numbers = M

One number = N

Let the second number be x.

Formula Used:

Average = (Sum of all observations) ÷ (Total number of observations)

Calculations:

⇒ M = (N + x) ÷ 2

⇒ 2 × M = N + x

⇒ 2M = N + x

⇒ x = 2M − N

∴ The correct answer is 2M-N.

Additional Information

Definition of Average (Arithmetic Mean)

It is the central value of a set of data, calculated by dividing the total sum by the count of values.

Sum Calculation

The sum of n observations is always n × Average. This is the base for solving missing number problems.

Weighted Average

When two groups with averages A1 and A2 and sizes n1 and n2 are combined, the new average is (n1A1 + n2A2) ÷ (n1 + n2).

Question 53

Cotton clothes are preferred in summer season because:

  1. AOption (a)

    cotton is unable to expose sweat to the atmosphere for evaporation

  2. BOption (b)

    cotton is a bad absorber of water and exposes sweat to atmosphere for evaporation

  3. COption (c)

    cotton is a good absorber of water and exposes sweat to atmosphere for evaporation

  4. DOption (d)

    cotton does not absorb sweat

View answer & explanation

Correct answer

Answer: (c)C.

cotton is a good absorber of water and exposes sweat to atmosphere for evaporation

Why this answer is correct

The correct answer is cotton is a good absorber of water and exposes sweat to atmosphere for evaporation.

Key Points

  • Cotton fabric is highly breathable, allowing air to circulate around the skin and sweat to evaporate.
  • Cotton is a natural fiber known for its ability to absorb moisture effectively.
  • When sweat is absorbed by cotton, it exposes a larger surface area for evaporation, which helps in cooling the body.
  • Evaporation of sweat from cotton clothes results in a cooling effect on the body, making it a preferred choice for summer wear.
  • Cotton’s moisture-wicking properties help in maintaining body temperature and prevent overheating during hot weather.

Additional Information

  • Evaporation Process
  • Evaporation is the process by which water changes from a liquid to a gas or vapor.
  • This process requires heat energy, which is taken from the surroundings, resulting in a cooling effect.
  • The efficiency of evaporation increases with higher temperatures and lower humidity levels.
  • Breathable Fabrics
  • Fabrics like cotton, linen, and some synthetic materials are designed to be breathable.
  • Breathable fabrics allow air to pass through them, aiding in moisture wicking and temperature regulation.
  • Such fabrics are ideal for active wear and hot weather clothing.
  • Moisture-Wicking
  • Moisture-wicking refers to the ability of a fabric to pull moisture away from the skin to the fabric's outer surface.
  • This helps in quicker evaporation and keeps the body dry and comfortable.
  • It is a key feature in athletic and performance clothing.
  • Thermal Regulation
  • Thermal regulation is the process by which the body maintains its core internal temperature.
  • Proper clothing can assist in thermal regulation by providing insulation and aiding in heat dissipation.
  • Cotton helps in maintaining thermal comfort by allowing heat to escape and sweat to evaporate.

Question 54

In the following number-pairs, the second number is obtained by applying certain mathematical operations to the first number. Which numbers should replace X and Y so that the pattern followed by the two numbers on the left side of :: is the same as that on the right side of ::?

(NOTE: Operations should be performed on the whole numbers, without breaking down the numbers into its constituent digits. E.g. 13 - Operations on 13 such as adding/subtracting/multiplying etc. to 13 can be performed. Breaking down 13 into 1 and 3 and then performing mathematical operations on 1 and 3 is not allowed.)

X : 72 :: 22 : Y

  1. AOption (a)

    X = 12, Y = 132

  2. BOption (b)

    X = 18, Y = 132

  3. COption (c)

    X = 18, Y = 96

  4. DOption (d)

    X = 12, Y = 110

View answer & explanation

Correct answer

Answer: (a)A.

X = 12, Y = 132

Why this answer is correct

The logic followed here is:

Logic: 1st number × 6 = 2nd number.

For, X : 72

⇒ X × 6 = 72

⇒ X = 72 ÷ 6 = 12.

Similarly,

For,  22 : Y

⇒ 22 × 6 = Y

⇒ 132 = Y.

Thus, X = 12, Y = 132

Hence, the correct answer is "Option 1".

Question 55

Electromagnetic Induction was discovered by:

  1. AOption (a)

    Edison

  2. BOption (b)

    Faraday

  3. COption (c)

    Newton

  4. DOption (d)

    Einstein

View answer & explanation

Correct answer

Answer: (b)B.

Faraday

Why this answer is correct

The correct answer is Faraday.

Key Points

  • Michael Faraday discovered the principle of electromagnetic induction in 1831.
  • Faraday’s law of electromagnetic induction states that an electromotive force is induced in a conductor when there is a change in the magnetic field around it.
  • This discovery laid the foundation for the development of electric generators and transformers.
  • Faraday's experiments demonstrated that a changing magnetic field could produce an electric current, which is the basic principle behind many types of electrical devices.

Additional Information

  • Electromagnetic Induction:
  • It is the production of voltage across a conductor situated in a changing magnetic field or a conductor moving through a stationary magnetic field.
  • Faraday’s law mathematically describes how a time varying magnetic field creates an electric field.
  • Electromagnetic induction is the working principle behind electrical components like inductors and transformers.
  • Lenz's Law:
  • Formulated by Heinrich Lenz in 1834, it states that the direction of the induced current will be such that it opposes the change in the magnetic field that produced it.
  • Lenz's Law is a consequence of the law of conservation of energy.
  • Applications of Electromagnetic Induction:
  • Used in the generation of electric power in power plants.
  • Essential in the functioning of transformers, which transfer electric energy between circuits.
  • Induction motors utilize this principle to convert electrical energy into mechanical energy.

Question 56

Which of the following is a property of liquids?

  1. AOption (a)

    Liquids have fixed shape.

  2. BOption (b)

    Liquids have no fixed volume.

  3. COption (c)

    Liquids are rigid.

  4. DOption (d)

    The rate of diffusion of liquids is higher than that of solids.

View answer & explanation

Correct answer

Answer: (d)D.

The rate of diffusion of liquids is higher than that of solids.

Why this answer is correct

The correct answer is The rate of diffusion of liquids is higher than that of solids..

Key Points

  • Liquids have no fixed shape but take the shape of the container they are in.
  • Liquids have a definite volume but no fixed shape.
  • The intermolecular forces in liquids are weaker than in solids, allowing for higher rates of diffusion.
  • The rate of diffusion in liquids is higher than that in solids due to the greater mobility of liquid molecules.

Additional Information

  • Diffusion
  • Diffusion is the process by which molecules spread from areas of high concentration to areas of low concentration.
  • In liquids, diffusion occurs faster than in solids because the molecules are more mobile.
  • Temperature affects the rate of diffusion; higher temperatures increase the rate.
  • Intermolecular Forces
  • Intermolecular forces are forces of attraction or repulsion between neighboring particles (atoms, molecules, or ions).
  • In liquids, these forces are weaker than in solids, enabling easier movement of particles.
  • Fluidity
  • Fluidity is the ability of a substance to flow and take the shape of its container.
  • Liquids and gases exhibit fluidity, with liquids being less compressible than gases.
  • Viscosity
  • Viscosity is a measure of a liquid's resistance to flow.
  • Liquids with high viscosity flow slower than those with low viscosity.

Question 57

Chami Murmu, an Indian environmental activist, was awarded the Padma Shri in 2024 for her work in founding the _____, which has planted over 3 million trees in Jharkhand. 

  1. AOption (a)

    Sahayogi Mahila Bagraisai

  2. BOption (b)

    Prakriti Raksha Abhiyan

  3. COption (c)

    Van Mahotsav Foundation

  4. DOption (d)

    Green India Mission

View answer & explanation

Correct answer

Answer: (a)A.

Sahayogi Mahila Bagraisai

Why this answer is correct

The correct answer is Sahayogi Mahila Bagraisai.

Key Points

  • Chami Murmu is an Indian environmental activist known for her significant contributions to environmental conservation.
  • She founded the organization Sahayogi Mahila Bagraisai, which focuses on tree plantation and environmental sustainability.
  • Under her leadership, the organization has planted over 3 million trees in the state of Jharkhand.
  • In recognition of her efforts, she was awarded the Padma Shri in 2024, one of India's highest civilian honors.

Additional Information

  • Padma Shri Award
  • It is the fourth highest civilian award in the Republic of India.
  • It is awarded to individuals for distinguished contributions in various fields including arts, education, industry, literature, science, sports, medicine, social service, and public affairs.
  • The award is announced annually on Republic Day.
  • Environmental Activism in India
  • India has a rich history of environmental activism, addressing issues such as deforestation, pollution, and wildlife conservation.
  • Notable environmental movements include the Chipko Movement and the Narmada Bachao Andolan.
  • Tree Plantation Initiatives
  • Tree plantation is a crucial activity in combating climate change and promoting biodiversity.
  • Various NGOs and government schemes in India focus on large-scale tree plantation drives.
  • Jharkhand
  • Jharkhand is a state in eastern India known for its diverse flora and fauna.
  • It is rich in mineral resources and has significant forest cover.

Question 58

Which of the following are small-sized in animal cells while in plant cells these are very large in size?

  1. AOption (a)

    Lysosomes

  2. BOption (b)

    Plastids

  3. COption (c)

    Golgi apparatus

  4. DOption (d)

    Vacuoles

View answer & explanation

Correct answer

Answer: (d)D.

Vacuoles

Why this answer is correct

The correct answer is Vacuoles.

Key Points

  • Vacuoles are membrane-bound organelles found in both plant and animal cells, but they differ significantly in size and function between the two.
  • In plant cells, vacuoles are typically very large and can occupy up to 90% of the cell's volume, serving as storage for nutrients, waste products, and helping in maintaining turgor pressure.
  • In animal cells, vacuoles are generally smaller and more numerous, primarily involved in storage, waste disposal, and intracellular digestion.
  • The large central vacuole in plant cells plays a crucial role in maintaining the cell's shape and structure by exerting internal pressure against the cell wall.

Additional Information

  • Lysosomes
  • Lysosomes are small organelles containing digestive enzymes, primarily involved in breaking down waste materials and cellular debris.
  • They are more prominent in animal cells and play a role in autophagy, the process of degrading and recycling cellular components.
  • Plastids
  • Plastids are a group of organelles found in plant cells and some algae, involved in the synthesis and storage of food.
  • Chloroplasts, a type of plastid, are responsible for photosynthesis in plant cells.
  • Golgi Apparatus
  • The Golgi apparatus is involved in modifying, sorting, and packaging proteins and lipids for secretion or use within the cell.
  • It is present in both plant and animal cells, but does not differ significantly in size between the two.

Question 59

The Lunar Polar Exploration Mission (LUPEX) is a planned collaborative lunar mission involving which two space agencies?

  1. AOption (a)

    ISRO and JAXA

  2. BOption (b)

    JAXA and CNSA

  3. COption (c)

    ISRO and NASA

  4. DOption (d)

    NASA and ESA

View answer & explanation

Correct answer

Answer: (a)A.

ISRO and JAXA

Why this answer is correct

The correct answer is ISRO and JAXA.

Key Points

  • The Lunar Polar Exploration Mission (LUPEX) is a collaborative lunar mission planned by the Indian Space Research Organisation (ISRO) and the Japan Aerospace Exploration Agency (JAXA).
  • LUPEX aims to explore the south pole region of the Moon to assess the presence of water and other resources.
  • The mission will include a lunar rover and a lander, with ISRO providing the lander and JAXA providing the rover.
  • LUPEX is part of broader international efforts to explore and utilize lunar resources to support future human and robotic missions.

Additional Information

  • ISRO (Indian Space Research Organisation)
  • ISRO is the space agency of the Government of India, headquartered in Bengaluru.
  • ISRO's primary objective is to harness space technology for national development while pursuing space science research and planetary exploration.
  • ISRO has successfully launched numerous missions, including the Chandrayaan and Mangalyaan missions.
  • JAXA (Japan Aerospace Exploration Agency)
  • JAXA is the Japanese national aerospace agency responsible for space and planetary exploration.
  • JAXA conducts various space missions, including satellite launches, human spaceflight, and lunar exploration.
  • JAXA has been involved in international collaborations, such as the International Space Station (ISS).
  • Lunar Exploration
  • Lunar exploration involves the study and exploration of the Moon's surface, resources, and environment.
  • It is critical for understanding the Moon's formation, geology, and potential for supporting future human missions.
  • Key objectives include mapping the lunar surface, studying the presence of water ice, and assessing the feasibility of lunar habitation.
  • Water on the Moon
  • The presence of water on the Moon, particularly in the form of ice, is crucial for future lunar exploration and colonization.
  • Water can be used for drinking, growing food, and producing oxygen for astronauts.
  • Water can also be broken down into hydrogen and oxygen, which can be used as rocket fuel for missions beyond the Moon.

Question 60

One atmosphere is equal to _____.

  1. AOption (a)

    1.01 × 10-5 Pa

  2. BOption (b)

    1.01 × 106 Pa

  3. COption (c)

    1.01 × 105 Pa

  4. DOption (d)

    1.01 × 10-6 Pa

View answer & explanation

Correct answer

Answer: (c)C.

1.01 × 105 Pa

Why this answer is correct

The correct answer is 1.01 × 105 Pa.

Key Points

  • One atmosphere (1 atm) is defined as being precisely equal to 101,325 Pa (Pascals).
  • For practical purposes, it is commonly approximated as 1.01 × 105 Pa.
  • This unit of pressure is widely used in various fields, including physics, chemistry, and engineering.
  • The value of 1 atm is derived from the average atmospheric pressure at sea level on Earth.
  • It serves as a standard reference for pressure measurements and calculations.

Additional Information

  • Pascal (Pa):
  • The SI unit of pressure, equivalent to one newton per square meter.
  • Bar:
  • Another unit of pressure, where 1 bar = 100,000 Pa, slightly less than 1 atm.
  • Standard Atmospheric Pressure:
  • Often used in aviation, meteorology, and other fields to denote the pressure at sea level, defined as 101,325 Pa.
  • Pressure Conversion:
  • 1 atm = 1013.25 millibars (mbar)
  • 1 atm = 760 mmHg (Torr)
  • 1 atm = 14.696 psi (pounds per square inch)

Question 61

Select the INCORRECT pair.

  1. AOption (a)

    Coal - digested in our body

  2. BOption (b)

    Plastic - does not breakdown by the action of bacteria

  3. COption (c)

    Rice - digested in our body

  4. DOption (d)

    Protein - digested in our body

View answer & explanation

Correct answer

Answer: (a)A.

Coal - digested in our body

Why this answer is correct

The correct answer is Coal - digested in our body.

Key Points

  • Coal is a fossil fuel formed from the remains of ancient plants and animals, and it is not a substance that can be digested by the human body.
  • The human digestive system is designed to break down organic materials like carbohydrates, proteins, and fats found in food, not inorganic substances like coal.
  • Materials that are undigestable by the human body are typically excreted as waste.
  • Ingesting coal or other non-digestible substances can lead to serious health issues such as gastrointestinal blockage or poisoning.

Additional Information

  • Digestion Process
  • Digestion begins in the mouth where food is mechanically broken down by chewing and mixed with saliva.
  • It continues in the stomach where gastric juices break down proteins and fats.
  • The small intestine is where most nutrient absorption occurs with the help of enzymes produced by the pancreas and bile from the liver.
  • Indigestible substances are passed into the large intestine where water is absorbed, and the remaining material is excreted as feces.
  • Fossil Fuels
  • Fossil fuels like coal, oil, and natural gas are formed over millions of years from the remains of plants and animals.
  • They are used primarily for energy production but are harmful to the environment due to greenhouse gas emissions.
  • Biodegradation
  • Biodegradation is the process by which organic substances are broken down by living organisms, typically bacteria.
  • Plastic and other synthetic materials are not easily biodegradable, leading to environmental pollution.
  • Human Health
  • Ingesting non-food substances can cause choking, poisoning, or internal injury.
  • Medical attention should be sought immediately if non-food items are ingested.

Question 62

Read the given statements and conclusions carefully. You have to take the given statements to be true even if they seem to be at variance from commonly known facts and decide which conclusion(s) logically follow(s) from the given statements.

Statements:

No car is a bus.

No bus is a plane.

Conclusions:

(I) No bus is a car.

(II) No car is a plane.

  1. AOption (a)

    Both conclusions I and II follow

  2. BOption (b)

    Only conclusion II follows

  3. COption (c)

    Only conclusion I follows

  4. DOption (d)

    Neither conclusion I nor II follows

View answer & explanation

Correct answer

Answer: (c)C.

Only conclusion I follows

Why this answer is correct

Statements:

No car is a bus.

No bus is a plane.

The least possible Venn diagram is given:

Conclusions:

(I) No bus is a car - True(Because, No car is a bus, it implies that no bus is car).

(II) No car is a plane - False(Because, there is no direct relation given between them, so it can be possible only).

Thus, Only conclusion I follows

Hence, the correct answer is "Option 3".

Question 63

Which of the following points always lie(s) on the principal axis of a spherical mirror?

i)Principal Focus

ii)Point of incidence

iii)Pole

  1. AOption (a)

    Only (i)

  2. BOption (b)

    Both (ii) and (iii)

  3. COption (c)

    Only (iii)

  4. DOption (d)

    Both (i) and (iii)

View answer & explanation

Correct answer

Answer: (d)D.

Both (i) and (iii)

Why this answer is correct

The correct answer is Both (i) and (iii).

Key Points

  • The Principal Focus of a spherical mirror is a point on the principal axis where light rays parallel to the principal axis converge (in concave mirrors) or appear to diverge from (in convex mirrors).
  • The Pole of a spherical mirror is the midpoint of the mirror's surface, lying on the principal axis.
  • Both the principal focus and the pole always lie on the principal axis of a spherical mirror.
  • The Point of incidence is the point where the light ray strikes the mirror, which does not necessarily lie on the principal axis.

Additional Information

  • Spherical Mirror
  • A spherical mirror is a mirror that has the shape of a piece cut out of a spherical surface. There are two types: concave and convex mirrors.
  • Concave mirrors converge light rays, while convex mirrors diverge them.
  • Principal Axis
  • The principal axis is an imaginary line that passes through the pole and the center of curvature of the spherical mirror.
  • It is the reference line for defining various properties and points related to the mirror.
  • Center of Curvature
  • The center of curvature is the center of the sphere from which the spherical mirror is a part.
  • It lies on the principal axis, at a distance equal to the radius of curvature from the pole.
  • Radius of Curvature
  • The radius of curvature is the radius of the sphere from which the mirror is a part.
  • It is twice the focal length in a spherical mirror.

Question 64

The value of 1118+7−27\frac{11}{18}+\frac{7}{-27} is :

  1. AOption (a)

    −1927\frac{-19}{27}

  2. BOption (b)

    1954\frac{19}{54}

  3. COption (c)

    −1954\frac{-19}{54}

  4. DOption (d)

    1927\frac{19}{27}

View answer & explanation

Correct answer

Answer: (b)B.

1954\frac{19}{54}

Why this answer is correct

Given:

Expression = 11/18 + 7/(−27)

Formula used:

Sum of fractions = (a/b) + (c/d) = (ad + bc) / (bd)

Calculations:

The given expression is 11/18 − 7/27

⇒ LCM of 18 and 27 = 54

⇒ (11 × 3)/54 − (7 × 2)/54

⇒ 33/54 − 14/54

⇒ (33 − 14) / 54

⇒ 19/54

∴ The correct answer is option (2).

Question 65

C2H2, C2H4, and C2H6 belong to which group of hydrocarbons?

  1. AOption (a)

    Alkyne, alkene, and alkane hydrocarbons, respectively

  2. BOption (b)

    Alkane, alkene, and alkyne hydrocarbons, respectively

  3. COption (c)

    Alkene, alkyne, and alkane hydrocarbons, respectively

  4. DOption (d)

    Alkane, alkyne, and alkene hydrocarbons, respectively

View answer & explanation

Correct answer

Answer: (a)A.

Alkyne, alkene, and alkane hydrocarbons, respectively

Why this answer is correct

The correct answer is Alkyne, alkene, and alkane hydrocarbons, respectively.

Key Points

  • C2H2 is known as acetylene and is classified as an alkyne hydrocarbon.
  • C2H4 is known as ethylene and is classified as an alkene hydrocarbon.
  • C2H6 is known as ethane and is classified as an alkane hydrocarbon.
  • Alkynes have a triple bond between carbon atoms, alkenes have a double bond, and alkanes have single bonds only.
  • These classifications are based on the type of carbon-carbon bonds present in the molecule.

Additional Information

  • Hydrocarbon Types:
  • Alkanes: Saturated hydrocarbons with only single bonds between carbon atoms (e.g., methane, ethane).
  • Alkenes: Unsaturated hydrocarbons with at least one double bond between carbon atoms (e.g., ethylene, propylene).
  • Alkynes: Unsaturated hydrocarbons with at least one triple bond between carbon atoms (e.g., acetylene, propyne).
  • Bond Characteristics:
  • Single bonds (sigma bonds) allow for free rotation around the bond axis.
  • Double bonds (one sigma and one pi bond) restrict rotation and create a planar structure.
  • Triple bonds (one sigma and two pi bonds) are linear and the shortest and strongest among the three types.
  • Uses of Hydrocarbons:
  • Alkanes are primarily used as fuels and lubricants.
  • Alkenes are used in the production of polymers and as intermediates in chemical reactions.
  • Alkynes are used in welding and as precursors to other chemicals.
  • Isomerism:
  • Hydrocarbons can exhibit structural isomerism, where compounds have the same molecular formula but different structures.
  • Geometric isomerism is seen in alkenes due to the restricted rotation around the double bond.

Question 66

Modes of reproduction in various organisms depend on the

  1. AOption (a)

    body design of the organisms

  2. BOption (b)

    nervous system of the organisms

  3. COption (c)

    respiratory pigments of the organisms

  4. DOption (d)

    nutritive strategy of the organisms

View answer & explanation

Correct answer

Answer: (a)A.

body design of the organisms

Why this answer is correct

The correct answer is body design of the organisms.

Key Points

  • The mode of reproduction in organisms is significantly influenced by their body structure and design.
  • Organisms with simpler body designs, such as single-celled organisms, typically reproduce asexually through processes like binary fission or budding.
  • More complex organisms, including most animals and plants, often reproduce sexually, involving specialized reproductive organs and processes.
  • The body design can determine the feasibility and efficiency of different reproductive strategies, ensuring the survival and adaptation of species.

Additional Information

  • Asexual Reproduction
  • Involves a single parent and produces offspring identical to the parent.
  • Common methods include binary fission, budding, fragmentation, and spore formation.
  • Examples include bacteria (binary fission) and yeast (budding).
  • Sexual Reproduction
  • Involves the combination of genetic material from two parents to produce genetically diverse offspring.
  • Involves specialized reproductive cells called gametes (sperm and egg).
  • Common in animals, plants, and many other organisms.
  • Reproductive Strategies
  • Reproductive strategies can be influenced by environmental factors, availability of mates, and evolutionary pressures.
  • Some organisms can switch between asexual and sexual reproduction based on environmental conditions.
  • Adaptation and Survival
  • Reproductive modes are crucial for the adaptation and survival of species in changing environments.
  • Genetic diversity from sexual reproduction can enhance the resilience of populations to diseases and environmental changes.

Question 67

Which of the following expressions gives the correct formula for mass by mass percentage of a solution?

  1. AOption (a)

    ((Volume of solute)/(Mass of solution)) × 100

  2. BOption (b)

    ((Mass of solvent)/(Mass of solution)) × 100

  3. COption (c)

    ((Mass of solute)/(Mass of solution)) × 100

  4. DOption (d)

    ((Mass of solute)/(Volume of solution)) × 100

View answer & explanation

Correct answer

Answer: (c)C.

((Mass of solute)/(Mass of solution)) × 100

Why this answer is correct

The correct answer is ((Mass of solute)/(Mass of solution)) × 100.

Key Points

  • The mass by mass percentage of a solution is calculated by dividing the mass of the solute by the mass of the solution and then multiplying by 100.
  • This formula is used to express the concentration of a solution, indicating the amount of solute present in a given mass of the solution.
  • The mass of the solution is the total mass of both the solute and the solvent combined.
  • Mass by mass percentage is often used in chemistry and industry to prepare solutions with precise concentrations.

Additional Information

  • Solution:
  • A homogeneous mixture composed of two or more substances.
  • In a solution, the solute is uniformly distributed within the solvent.
  • Solute:
  • The substance that is dissolved in a solution.
  • For example, in a saltwater solution, salt is the solute.
  • Solvent:
  • The substance that dissolves the solute to form a solution.
  • Water is known as the "universal solvent" because it can dissolve many substances.
  • Concentration:
  • The amount of a substance (solute) present in a certain volume or mass of the solution or solvent.
  • It can be expressed in various ways, including mass by mass percentage, volume by volume percentage, and molarity.

Question 68

Which of the following terms defines the ability of metals to be drawn into thin wires?

  1. AOption (a)

    Malleability

  2. BOption (b)

    Ductility

  3. COption (c)

    Neither malleability nor ductility

  4. DOption (d)

    Both malleability and ductility

View answer & explanation

Correct answer

Answer: (b)B.

Ductility

Why this answer is correct

The correct answer is Ductility.

Key Points

  • Ductility is the property of a material that allows it to be drawn into thin wires.
  • This property is most commonly observed in metals such as gold, silver, copper, and aluminum.
  • Gold is known to be one of the most ductile metals, capable of being drawn into very fine wires.
  • The measure of ductility is typically expressed as a percentage of elongation or the reduction of area in a tensile test.
  • Ductility is essential for manufacturing processes like wire drawing and tube making.

Additional Information

  • Malleability
  • Malleability is the ability of a material to be hammered or rolled into thin sheets without breaking.
  • Like ductility, malleability is a property of metals, allowing them to be shaped and formed.
  • Gold and silver are also highly malleable, making them useful for various industrial and jewelry applications.
  • Tensile Strength
  • Tensile strength is the maximum amount of tensile stress that a material can withstand before failure.
  • It is an important property for materials that are used in structures and machines.
  • High tensile strength materials are often also ductile, but this is not always the case.
  • Brittleness
  • Brittleness is the tendency of a material to break or shatter without significant deformation when under stress.
  • Brittle materials, like glass, ceramics, and some polymers, have low ductility and malleability.
  • These materials are often used where high hardness and low deformability are required.
  • Plasticity
  • Plasticity is the ability of a material to undergo permanent deformation without breaking.
  • This property is crucial for processes such as forging, molding, and stamping.
  • Metals and polymers typically exhibit high plasticity.

Question 69

Select the INCORRECT statement from the following options.

  1. AOption (a)

    The kinetic energy is the energy possessed by an object due to its position.

  2. BOption (b)

    The kinetic energy of an object increases with the increase of its mass. 

  3. COption (c)

    The kinetic energy is the energy possessed by an object due to its motion.

  4. DOption (d)

    The kinetic energy of an object increases with the increase of its velocity.

View answer & explanation

Correct answer

Answer: (a)A.

The kinetic energy is the energy possessed by an object due to its position.

Why this answer is correct

The correct answer is Option 1.

Key Points

  • The kinetic energy of an object is the energy it possesses due to its motion, not its position.
  • Kinetic energy increases with the mass of the object; the formula is KE = 0.5 * m * v^2, where m is mass and v is velocity.
  • Kinetic energy also increases with the square of the object's velocity.
  • Potential energy, not kinetic energy, is related to the position of an object in a force field, such as gravity.

Additional Information

  • Kinetic Energy (KE)
  • Defined as the energy that an object possesses due to its motion.
  • The SI unit of kinetic energy is the Joule (J).
  • Kinetic energy is a scalar quantity; it has magnitude but no direction.
  • Examples of kinetic energy include a moving car, a flying airplane, and flowing water.
  • Potential Energy (PE)
  • Energy possessed by an object due to its position or state.
  • Examples include gravitational potential energy, elastic potential energy, and chemical potential energy.
  • Potential energy can be converted into kinetic energy and vice versa.
  • Work-Energy Theorem
  • The work done on an object is equal to the change in its kinetic energy.
  • Mathematically, W = ΔKE, where W is work done and ΔKE is the change in kinetic energy.
  • Law of Conservation of Energy
  • States that energy cannot be created or destroyed but can only be transformed from one form to another.
  • In a closed system, the total energy remains constant.

Question 70

When the selling price of a TV is ​₹ 18,700, the shopkeeper incurs a loss of 15%. What should be the selling price of that TV so as to gain 15%?

  1. AOption (a)

    ​₹ 43,200​

  2. BOption (b)

    ​₹ 34,200

  3. COption (c)

    ₹ 19,800

  4. DOption (d)

    ₹ 25,300

View answer & explanation

Correct answer

Answer: (d)D.

₹ 25,300

Why this answer is correct

Shortcut Trick

Loss of 15% means SP1 = 100% − 15% = 85%.

Gain of 15% means SP2 = 100% + 15% = 115%.

According to the question, 85% = ₹ 18,700.

Unitary method: 1% = 18,700 ÷ 85 = ₹ 220.

Therefore, 115% = 220 × 115 = ₹ 25,300.

∴ The correct answer is ₹ 25,300.

Alternate Method

Given: First Selling Price (SP1) = ₹ 18,700, Loss% = 15%, Required Profit% = 15%.

Formulas: CP = SP × 100 ÷ (100 − Loss%) | SP = CP × (100 + Gain%) ÷ 100

⇒ Cost Price (CP) = 18,700 × 100 ÷ (100 − 15) = 18,700 × 100 ÷ 85 = ₹ 22,000.

⇒ New Selling Price (SP2) = 22,000 × (100 + 15) ÷ 100 = 22,000 × 115 ÷ 100.

⇒ SP2 = 220 × 115 = ₹ 25,300.

∴ The correct answer is ₹ 25,300.

Additional Information

Cost Price (CP)

The price at which an article is purchased. It is always considered as 100% in percentage calculations of profit or loss.

Selling Price (SP)

The price at which an article is sold. SP = CP + Profit OR SP = CP − Loss.

Question 71

If the mode of a data exceeds its mean by 16.2, then the mode exceeds the median by _______. (Use empirical formula to find the answer.)

  1. AOption (a)

    10.8

  2. BOption (b)

    12.4

  3. COption (c)

    10.2

  4. DOption (d)

    8.25

View answer & explanation

Correct answer

Answer: (a)A.

10.8

Why this answer is correct

Shortcut Trick

Empirical relationship: (Mode − Mean) = 3 × (Median − Mean)

Also, (Mode − Median) = 2/3 × (Mode − Mean)

⇒ Required value = 2/3 × 16.2

⇒ Required value = 2 × 5.4 = 10.8

∴ The correct answer is 10.8.

Alternate Method

Given:

Mode − Mean = 16.2

Formula Used:

The Empirical Relationship between measures of central tendency is:

Mode = 3 × Median − 2 × Mean

Calculations:

⇒ Mode = 3 × Median − 2 × Mean

⇒ Mode + 2 × Mean = 3 × Median

⇒ Subtract 3 × Median from both sides and rearrange to find Mode − Median:

⇒ Mode − Mean = 16.2 (Equation 1)

⇒ Mean = Mode − 16.2

⇒ Substitute Mean in Empirical formula: Mode = 3 × Median − 2 × (Mode − 16.2)

⇒ Mode = 3 × Median − 2 × Mode + 32.4

⇒ 3 × Mode − 32.4 = 3 × Median

⇒ Divide by 3: Mode − 10.8 = Median

⇒ Mode − Median = 10.8

∴ The correct answer is 10.8.

Additional Information

Empirical Formula

For a moderately skewed distribution, the relationship is Mode = 3 Median − 2 Mean.

Symmetrical Distribution

In a perfectly symmetrical distribution (like the Normal Distribution), Mean = Median = Mode.

Measures of Central Tendency

Mean is the average, Median is the middle value, and Mode is the most frequent value in a data set.

Question 72

The focal length of a spherical mirror is 12 cm, then the radius of curvature of this mirror will be:

  1. AOption (a)

    24 cm

  2. BOption (b)

    3 cm

  3. COption (c)

    2 cm

  4. DOption (d)

    6 cm

View answer & explanation

Correct answer

Answer: (a)A.

24 cm

Why this answer is correct

The correct answer is 24 cm.

Key Points

  • The radius of curvature (R) of a spherical mirror is twice the focal length (f).
  • Given the focal length (f) is 12 cm, the formula R = 2f can be applied.
  • By substituting f = 12 cm into the formula, we get R = 2 * 12 cm.
  • Thus, the radius of curvature (R) is 24 cm.
  • This relationship holds true for both concave and convex mirrors.

Additional Information

  • Spherical Mirrors:
  • Spherical mirrors are mirrors with a consistent curvature, such as concave and convex mirrors.
  • Concave mirrors curve inward, focusing light to a point, and are used in applications like telescopes.
  • Convex mirrors curve outward, spreading light out, and are used for wide-angle viewing like in vehicle side mirrors.
  • Focal Length (f):
  • The focal length is the distance between the mirror's surface and its focal point, where parallel rays of light either converge or appear to diverge.
  • In concave mirrors, the focal point is in front of the mirror; in convex mirrors, it is behind the mirror.
  • Radius of Curvature (R):
  • The radius of curvature is the radius of the sphere from which the spherical mirror is a segment.
  • The center of this sphere is called the center of curvature, and the radius connects it to any point on the mirror.
  • Mirror Equation:
  • The mirror equation relates the object distance (u), image distance (v), and the focal length (f): 1/f = 1/u + 1/v.
  • This equation is essential for understanding image formation by spherical mirrors.

Question 73

Seven boxes, A, B, C, D, E, F and G, are kept one over the other but not necessarily in the same order. Only C is kept above D. Only two boxes are kept between D and F. Only G is kept below A. B is not kept immediately above F. Which box is kept fourth from the top ?

  1. AOption (a)

    E

  2. BOption (b)

    B

  3. COption (c)

    H

  4. DOption (d)

    D

View answer & explanation

Correct answer

Answer: (a)A.

E

Why this answer is correct

Given: Seven boxes, A, B, C, D, E, F and G, are kept one over the other but not necessarily in the same order.

Only C is kept above D. Only two boxes are kept between D and F.

C
D
F

Only G is kept below A. B is not kept immediately above F. 

C
D
B
F
A
G

Final arrangement,

C
D
B
E
F
A
G

Thus, E is the box is kept fourth from the top.

Hence, the correct answer is "Option 1".

Question 74

The value of tan A + 1tan⁡A\rm \frac{1}{\tan A} is :

  1. AOption (a)

    cosec A sin A

  2. BOption (b)

    cosec A sec A

  3. COption (c)

    cosec A cot A

  4. DOption (d)

    cos A sec A

View answer & explanation

Correct answer

Answer: (b)B.

cosec A sec A

Why this answer is correct

Shortcut Trick

Use Value Substitution: Let A = 45°.

tan 45° + 1/tan 45° = 1 + 1/1 = 2.

Check options: (2) cosec 45° × sec 45° = √2 × √2 = 2. Match found.

∴ The correct answer is cosec A sec A.

Alternate Method

Given: tan A + 1/tan A

Formula Used: tan A = sin A/cos A and sin2A + cos2A = 1

⇒ tan A + 1/tan A = tan A + cot A

⇒ (sin A / cos A) + (cos A / sin A)

⇒ (sin2A + cos2A) / (sin A cos A)

⇒ 1 / (sin A cos A)

⇒ (1 / sin A) × (1 / cos A)

⇒ cosec A sec A

∴ The correct answer is cosec A sec A.

Additional Information

Reciprocal Identities

cosec A = 1/sin A, sec A = 1/cos A, and cot A = 1/tan A are the primary reciprocal ratios.

Pythagorean Identities

sin2A + cos2A = 1, 1 + tan2A = sec2A, and 1 + cot2A = cosec2A.

Common Result

The expression tan A + cot A is frequently encountered and simplifies directly to sec A cosec A.

Question 75

In this question, a statement is followed by two courses of action, numbered I and II. You must assume everything in the statement to be true and on the basis of the information given in the statement, decide which of the courses of action logically follow(s) for pursuing.

Statement:

The bee population in the region has been steadily declining due to the widespread use of pesticides in agriculture.

Courses of Action:

I. Introduce regulations that restrict the use of certain pesticides during peak pollination seasons.

II. Establish urban beekeeping programmes to artificially boost the bee population and pollination efforts.

  1. AOption (a)

    Only I follows

  2. BOption (b)

    Only II follows

  3. COption (c)

    Neither I nor II follows

  4. DOption (d)

    Both I and II follow

View answer & explanation

Correct answer

Answer: (d)D.

Both I and II follow

Why this answer is correct

Statement:

The bee population in the region has been steadily declining due to the widespread use of pesticides in agriculture.

Courses of Action:

I. Introduce regulations that restrict the use of certain pesticides during peak pollination seasons - Follows(Regulating pesticide use during peak pollination seasons can help reduce harm to bees, allowing them to thrive and continue their ecological role in pollination).

II. Establish urban beekeeping programmes to artificially boost the bee population and pollination efforts - Follows(Urban beekeeping can help counteract the decline in bee populations by providing safe habitats, though it does not directly address the root cause (pesticides).

Thus, Both Course of Action I and II follow.

Course I directly addresses the root cause, while Course II provides an alternative solution to sustain the bee population.

Hence, the correct answer is "Option 4".

Question 76

At what rate (in percentage) per annum on simple interest will a sum of money double itself in 8 years?

  1. AOption (a)

    12.5%

  2. BOption (b)

    5.6%

  3. COption (c)

    6.25%

  4. DOption (d)

    2.5%

View answer & explanation

Correct answer

Answer: (a)A.

12.5%

Why this answer is correct

Shortcut Trick

For a sum to double itself, the Simple Interest must be equal to the Principal (100%).

Shortcut Formula: Rate (R) = 100 ÷ Time (T)

⇒ R = 100 ÷ 8

⇒ R = 12.5%

∴ The correct answer is 12.5%.

Alternate Method

Given:

Time (T) = 8 years

Let Principal (P) = 100

Amount (A) = 2 × 100 = 200 (as it doubles)

Formula Used:

Simple Interest (SI) = A − P

SI = (P × R × T) ÷ 100

Calculations:

⇒ SI = 200 − 100 = 100

⇒ 100 = (100 × R × 8) ÷ 100

⇒ 100 = 8R

⇒ R = 100 ÷ 8

⇒ R = 12.5%

∴ The correct answer is 12.5%.

Additional Information

General Formula for n-times growth

If a sum becomes 'n' times in 'T' years, then Rate R = [(n − 1) × 100] ÷ T.

Simple Interest vs Amount

Simple Interest is calculated only on the Principal, while Amount is the sum of Principal and Interest (A = P + SI).

Constant Nature of SI

In Simple Interest, the interest earned remains the same every year if the rate and principal are constant.

Question 77

If an object with a mass of 0.1 kg moves with a uniform velocity of 2 ms-1, its kinetic energy is

  1. AOption (a)

    0.4 joule

  2. BOption (b)

    0.1 joule

  3. COption (c)

    0.2 joule

  4. DOption (d)

    0.05 joule

View answer & explanation

Correct answer

Answer: (c)C.

0.2 joule

Why this answer is correct

The correct answer is 0.2 joule.

Key Points

  • Kinetic energy is the energy that an object possesses due to its motion.
  • The formula for calculating kinetic energy (KE) is: K.E=12mv2K.E=\frac{1}{2}mv^2
  • In this problem, the mass (m) of the object is 0.1 kg.
  • The velocity (v) of the object is 2 m/s.
  • Using the formula:
  • KE = 1/2mv2 = 1/2 × 0.1 × (2)2 = 1/2 × 0.1 × 4 = 0.2 J

Additional Information

  • Energy:
  • Energy is the capacity to do work and is measured in joules (J) in the International System of Units (SI).
  • Different forms of energy include kinetic energy, potential energy, thermal energy, chemical energy, and more.
  • Mass:
  • Mass is a measure of the amount of matter in an object and is measured in kilograms (kg) in the SI unit.
  • It is an intrinsic property of an object and does not change with its location.
  • Velocity:
  • Velocity is the speed of an object in a specific direction and is measured in meters per second (m/s) in the SI unit.
  • It is a vector quantity, meaning it has both magnitude and direction.
  • Work:
  • Work is done when a force applied to an object moves it through a distance.
  • It is calculated as the product of the force and the distance moved in the direction of the force, measured in joules (J).

Question 78

To move an object on a horizontal table, one needs to apply:

  1. AOption (a)

    balanced force

  2. BOption (b)

    an equal amount of perpendicular forces on the object in both upward and downward directions

  3. COption (c)

    unbalanced force

  4. DOption (d)

    only a single force perpendicular to the object

View answer & explanation

Correct answer

Answer: (c)C.

unbalanced force

Why this answer is correct

The correct answer is unbalanced force.

Key Points

  • An unbalanced force is necessary to change the state of motion of an object, as per Newton's First Law of Motion.
  • Applying an unbalanced force to an object on a horizontal table overcomes the frictional force between the object and the table surface.
  • When the forces acting on an object are unbalanced, they cause a change in the object's velocity, resulting in acceleration.
  • The direction of the unbalanced force determines the direction in which the object will move.
  • An unbalanced force implies that the net force acting on the object is not zero, leading to motion.

Additional Information

  • Newton's First Law of Motion (Law of Inertia)
  • States that an object will remain at rest or in uniform motion in a straight line unless acted upon by an external unbalanced force.
  • Highlights the concept of inertia, which is the tendency of objects to resist changes in their state of motion.
  • Friction
  • A force that opposes the relative motion or tendency of such motion of two surfaces in contact.
  • Can be reduced by applying lubricants or by using smoother surfaces.
  • Balanced Forces
  • When two forces acting on an object are equal in size but opposite in direction, they are balanced forces.
  • Balanced forces do not cause a change in the motion of an object.
  • Net Force
  • The overall force acting on an object when all the individual forces acting on it are combined.
  • If the net force is not zero, the forces are unbalanced, leading to a change in the object's motion.

Question 79

What is the full form of CNG and LPG, respectively?

  1. AOption (a)

    Compressed Natural Gas and Liquefied Pressured Gas

  2. BOption (b)

    Compressed Neutral Gas and Liquefied Pressured Gas

  3. COption (c)

    Compressed Neutral Gas and Liquefied Petroleum Gas

  4. DOption (d)

    Compressed Natural Gas and Liquefied Petroleum Gas

View answer & explanation

Correct answer

Answer: (d)D.

Compressed Natural Gas and Liquefied Petroleum Gas

Why this answer is correct

The correct answer is Compressed Natural Gas and Liquefied Petroleum Gas.

Key Points

  • Compressed Natural Gas (CNG) is a fuel gas mainly composed of methane, compressed to less than 1% of its volume at standard atmospheric pressure.
  • Liquefied Petroleum Gas (LPG) consists mainly of propane, butane, or a mixture of these gases, and is stored in liquid form under moderate pressure.
  • CNG is primarily used as an alternative to gasoline, diesel, and propane fuel in vehicles.
  • LPG is commonly used for heating, cooking, and as a fuel for certain vehicles and equipment.
  • Both CNG and LPG are considered cleaner alternatives to other fossil fuels, emitting lower levels of pollutants.

Additional Information

  • Methane (CH4)
  • Methane is a colorless, odorless, and highly flammable gas, which is the main component of natural gas.
  • It is used as a fuel and is a major greenhouse gas, contributing to global warming.
  • CNG is primarily composed of methane, making it a cleaner burning fuel compared to gasoline and diesel.
  • Propane (C3H8)
  • Propane is a three-carbon alkane gas, normally compressed and stored as a liquid.
  • It is widely used in heating, cooking, and as a fuel for engines.
  • Propane is a major component of LPG.
  • Butane (C4H10)
  • Butane is a four-carbon alkane gas, usually found mixed with propane in LPG.
  • It is used in lighters, portable stoves, and as a propellant in aerosol sprays.
  • Butane is another key component of LPG.
  • Environmental Impact
  • CNG vehicles produce lower emissions of carbon monoxide, nitrogen oxides, and particulate matter compared to gasoline and diesel vehicles.
  • LPG burns more cleanly than many other fossil fuels, resulting in fewer greenhouse gases and pollutants.
  • Both CNG and LPG contribute to reducing the carbon footprint when used as alternative fuels.

Question 80

Consider the following statements about a mixture and determine which of the statements is/are correct.

  1. A mixture has a variable composition.
  2. In compounds, the composition of each new substance is always fixed.
  3. A mixture shows the properties of the constituent substances.
  1. AOption (a)

    Only 2 and 3

  2. BOption (b)

    Only 1 and 2

  3. COption (c)

    1, 2 and 3

  4. DOption (d)

    Only 1

View answer & explanation

Correct answer

Answer: (c)C.

1, 2 and 3

Why this answer is correct

The correct answer is 1, 2 and 3.

Key Points

  • A mixture has a variable composition, meaning the proportions of its components can vary.
  • In compounds, the composition of each new substance is always fixed, with elements combined in definite ratios.
  • A mixture exhibits the properties of the substances that make it up, without chemical bonding between the components.
  • Mixtures can be separated into their individual components by physical means such as filtration, distillation, or evaporation.
  • Examples of mixtures include air, which is a mixture of gases, and saltwater, which is a mixture of salt and water.

Additional Information

  • Homogeneous Mixtures
  • These mixtures have a uniform composition throughout. Examples include solutions like sugar in water.
  • The different components of a homogeneous mixture cannot be easily distinguished.
  • Heterogeneous Mixtures
  • These mixtures have a non-uniform composition. Examples include mixtures like sand in water.
  • The different components of a heterogeneous mixture can be easily distinguished.
  • Physical Separation Techniques
  • Filtration: Used to separate solids from liquids in a heterogeneous mixture.
  • Distillation: Used to separate liquids based on differences in boiling points.
  • Evaporation: Used to separate a dissolved solid from a liquid.
  • Compounds vs. Mixtures
  • Compounds are substances formed when two or more elements are chemically bonded together, with fixed composition.
  • Mixtures involve physical blending of two or more substances without chemical bonding.

Question 81

(x − y) (x + y) (x2 + y2) (x4 + y4) is equal to :

  1. AOption (a)

    x8 + y8

  2. BOption (b)

    x16 + y16

  3. COption (c)

    x16 - y16

  4. DOption (d)

    x8 - y8

View answer & explanation

Correct answer

Answer: (d)D.

x8 - y8

Why this answer is correct

Shortcut Trick

Apply the Difference of Squares formula (a − b)(a + b) = a2 − b2 repeatedly.

(x − y)(x + y) → x2 − y2

(x2 − y2)(x2 + y2) → x4 − y4

(x4 − y4)(x4 + y4) → x8 − y8

∴ The correct answer is x8 − y8.

Alternate Method

Given: (x − y) (x + y) (x2 + y2) (x4 + y4)

Formula Used: (a − b)(a + b) = a2 − b2

⇒ Step 1: Multiply the first two terms

⇒ (x − y)(x + y) = x2 − y2

⇒ Step 2: Multiply the result with the third term

⇒ (x2 − y2)(x2 + y2) = (x2)2 − (y2)2 = x4 − y4

⇒ Step 3: Multiply the result with the fourth term

⇒ (x4 − y4)(x4 + y4) = (x4)2 − (y4)2 = x8 − y8

∴ The correct answer is x8 − y8.

Additional Information

Algebraic Identities

The formula (a − b)(a + b) = a2 − b2 is used for factorization and simplification of polynomials.

Laws of Exponents

When a power is raised to another power, the exponents are multiplied: (xa)b = xa × b.

Generalization

For n terms of the form (x2<sup>k</sup> + y2<sup>k</sup>), the product (x−y)(x+y)(x2+y2)...(x2<sup>n-1</sup>+y2<sup>n-1</sup>) = x2<sup>n</sup> − y2<sup>n</sup>.

Question 82

As of October 2024, India is the home to _______ UNESCO World Heritage Sites.

  1. AOption (a)

    33

  2. BOption (b)

    63

  3. COption (c)

    53

  4. DOption (d)

    43

View answer & explanation

Correct answer

Answer: (d)D.

43

Why this answer is correct

The correct answer is 43.

Key Points

  • As of October 2024, India is home to 43 UNESCO World Heritage Sites.
  • India's World Heritage Sites include 35 cultural, 7 natural, and 1 mixed properties as recognized by UNESCO.
  • The latest addition to India's list was the “Moidams: The Mound-Burial System of the Ahom Dynasty” from Assam, which was inscribed in July 2024.
  • With this, India now has 43 sites on the World Heritage List and 62 more on UNESCO’s Tentative List.
  • The UNESCO World Heritage Sites in India span a wide range of historical periods and cultural significance, from ancient monuments to modern marvels.
  • India ranks sixth in the world in terms of the number of World Heritage Sites.

Additional Information

  • UNESCO World Heritage Sites
  • A UNESCO World Heritage Site is a landmark or area with legal protection by an international convention administered by the United Nations Educational, Scientific, and Cultural Organization (UNESCO).
  • These sites are designated as having cultural, historical, scientific, or other forms of significance.
  • The program began with the Convention Concerning the Protection of the World Cultural and Natural Heritage, which was adopted by UNESCO in 1972.
  • As of 2023, there are over 1,100 World Heritage Sites across the globe.
  • Criteria for Selection
  • To be selected, a World Heritage Site must be of outstanding universal value and meet at least one of ten selection criteria, such as representing a masterpiece of human creative genius or containing superlative natural phenomena.
  • These criteria are regularly revised by the World Heritage Committee to reflect the evolution of the World Heritage concept itself.
  • India's Representation
  • India has a rich cultural and natural heritage, which is represented by its significant number of World Heritage Sites.
  • The Taj Mahal, one of the most recognized monuments in the world, is a notable UNESCO World Heritage Site in India.
  • Other significant sites include the Sun Temple at Konarak, the Group of Monuments at Hampi, and the Great Himalayan National Park.

Question 83

A retailer permits a trade discount of 15%, followed by a cash discount of 20%, on an article. The net percentage of discount is :

  1. AOption (a)

    34%

  2. BOption (b)

    31%

  3. COption (c)

    33%

  4. DOption (d)

    32%

View answer & explanation

Correct answer

Answer: (d)D.

32%

Why this answer is correct

Shortcut Trick

Net discount for successive discounts a% and b% is given by the formula: (a + b − ab ÷ 100)%.

Given trade discount a = 15% and cash discount b = 20%.

Net Discount = (15 + 20 − (15 × 20) ÷ 100)%.

Net Discount = (35 − 300 ÷ 100)% = (35 − 3)% = 32%.

∴ The correct answer is 32%.

Alternate Method

Given: First discount = 15%, Second discount = 20%.

Formulas: Net Discount% = (Initial Price − Final Price) ÷ Initial Price × 100 | Selling Price = Marked Price × (100 − D1)% × (100 − D2)%

⇒ Let the Marked Price (MP) of the article be 100.

⇒ After 15% trade discount, Price = 100 − 15% of 100 = 85.

⇒ After 20% cash discount, Selling Price (SP) = 85 − 20% of 85.

⇒ SP = 85 − (20 ÷ 100 × 85) = 85 − 17 = 68.

⇒ Net Discount = MP − SP = 100 − 68 = 32.

⇒ Net Discount percentage = (32 ÷ 100) × 100 = 32%.

∴ The correct answer is 32%.

Additional Information

Trade Discount vs Cash Discount

A trade discount is offered to all buyers in the same category, while a cash discount is provided to encourage immediate or early payment.

Successive Discounts

When more than one discount is offered on an article, they are calculated consecutively. The net percentage is always less than the simple sum of individual percentages.

Question 84

Find the fourth proportional of 15, 25 and 12.

  1. AOption (a)

    15

  2. BOption (b)

    30

  3. COption (c)

    25

  4. DOption (d)

    20

View answer & explanation

Correct answer

Answer: (d)D.

20

Why this answer is correct

Shortcut Trick

For fourth proportional of a, b, c → d = (b × c) ÷ a

Here a = 15, b = 25, c = 12

Fourth Proportional = (25 × 12) ÷ 15 = 300 ÷ 15 = 20

∴ The correct answer is 20.

Alternate Method

Given: First number (a) = 15, Second number (b) = 25, Third number (c) = 12

Formula Used: a : b :: c : d ⇒ a/b = c/d

⇒ Let the fourth proportional be x.

⇒ 15 : 25 = 12 : x

⇒ 15 × x = 25 × 12

⇒ 15x = 300

⇒ x = 300 ÷ 15

⇒ x = 20

∴ The correct answer is 20.

Additional Information

Mean Proportional

The mean proportional between two numbers a and b is √(a × b).

Third Proportional

If a : b :: b : c, then c is called the third proportional, where c = b2 ÷ a.

Direct Proportion

Two quantities are in direct proportion if an increase in one leads to a corresponding increase in the other (x/y = k).

Question 85

An object weighs 60 N when measured on the Earth. What would be its weight when measured on the moon?

(Given, acceleration due to gravity (g) of the moon is 1/6 th of the g of the earth)

  1. AOption (a)

    70 N

  2. BOption (b)

    10 N

  3. COption (c)

    40 N

  4. DOption (d)

    60 N

View answer & explanation

Correct answer

Answer: (b)B.

10 N

Why this answer is correct

The correct answer is 10 N.

Key Points

  • The weight of an object depends on the gravitational force acting on it, which varies from planet to planet.
  • On the Earth, the object weighs 60 N due to Earth's gravitational acceleration (g ≈ 9.81 m/s²).
  • The Moon's gravitational acceleration is approximately 1/6th that of Earth's (g ≈ 1.63 m/s²).
  • Weight on the Moon is calculated by dividing the Earth's weight by 6 (60 N ÷ 6 = 10 N).
  • Therefore, the object would weigh 10 N on the Moon.

Additional Information

  • Gravitational Force:
  • It is the force that attracts a body towards the center of the Earth or any other celestial body.
  • The gravitational force on the Moon is about 1/6th of that on Earth.
  • Weight vs. Mass:
  • Weight is the force exerted by gravity on an object (measured in Newtons).
  • Mass is the amount of matter in an object (measured in kilograms) and remains constant regardless of location.
  • Newton's Second Law of Motion:
  • It states that the force acting on an object is equal to the mass of the object multiplied by its acceleration (F = ma).
  • On the Moon, the acceleration due to gravity is less, hence the weight is less for the same mass.
  • Scientific Significance:
  • Understanding weight differences on different celestial bodies is crucial for space exploration and missions.
  • Astronauts need to adjust for these differences during lunar missions.

Question 86

The number of solutions to the pair of linear equations 5x - 3y = 7 and 7x + 4y = 18 is:

  1. AOption (a)

    one

  2. BOption (b)

    none

  3. COption (c)

    infinite

  4. DOption (d)

    three

View answer & explanation

Correct answer

Answer: (a)A.

one

Why this answer is correct

Shortcut Trick

Check the ratio of coefficients of x and y for the given linear equations.

Ratio of x-coefficients (a1/a2) = 5/7

Ratio of y-coefficients (b1/b2) = −3/4

Since 5/7 ≠ −3/4, the lines intersect at exactly one point.

∴ The correct answer is one.

Alternate Method

Given:

Equation 1: 5x − 3y − 7 = 0 (a1 = 5, b1 = −3, c1 = −7)

Equation 2: 7x + 4y − 18 = 0 (a2 = 7, b2 = 4, c2 = −18)

Formula Used:

For a unique solution: a1/a2 ≠ b1/b2

For no solution: a1/a2 = b1/b2 ≠ c1/c2

For infinitely many solutions: a1/a2 = b1/b2 = c1/c2

Calculations:

⇒ a1/a2 = 5/7

⇒ b1/b2 = −3/4

⇒ 5/7 ≠ −3/4

⇒ a1/a2 ≠ b1/b2

∴ The correct answer is one.

Additional Information

Consistent System

A system of equations is consistent if it has at least one solution (either a unique solution or infinite solutions).

Inconsistent System

A system is inconsistent if there is no solution, which occurs when the lines are parallel (a1/a2 = b1/b2 ≠ c1/c2).

Graphical Representation

A unique solution corresponds to intersecting lines, while infinite solutions correspond to coincident lines.

Question 87

Read the given statements and conclusions carefully. You have to take the given statements to be true even if they seem to be at variance from commonly known facts and decide which conclusion(s) logically follow(s) from the given statements.

Statements:

All apples are mangoes.

Some mangoes are lemons.

Conclusions:

(I) At least some mangoes are apples.

(II) Some apples are lemons.

  1. AOption (a)

    Only conclusion II follows

  2. BOption (b)

    Both conclusions I and II follow

  3. COption (c)

    Neither conclusion I nor II follows

  4. DOption (d)

    Only conclusion I follows

View answer & explanation

Correct answer

Answer: (d)D.

Only conclusion I follows

Why this answer is correct

Statements:

All apples are mangoes.

Some mangoes are lemons.

The least possible venn diagram is given:

Conclusions:

(I) At least some mangoes are apples - True(Because, All apples are mangoes it implies that some mangoes are apples as well).

(II) Some apples are lemons - False(Because, there is no direct relation is given between them, so it can be possible only).

Thus, Only conclusion I follows.

Hence, the correct answer is "Option 4"

Question 88

Out of an earning of ₹ 720, Rama spends 65%. How much does she save?

  1. AOption (a)

    ₹ 252

  2. BOption (b)

    ₹ 390

  3. COption (c)

    ₹ 350

  4. DOption (d)

    ₹ 316

View answer & explanation

Correct answer

Answer: (a)A.

₹ 252

Why this answer is correct

Shortcut Trick

Total Earnings = 100%

Expenditure = 65% → Savings = 100% − 65% = 35%

Savings = 35% of ₹ 720 = 0.35 × 720

Savings = 7.2 × 35 = 252

∴ The correct answer is ₹ 252.

Alternate Method

Given:

Total Earnings = ₹ 720

Spending Percentage = 65%

Formula Used:

Savings = Total Earnings − Expenditure

Expenditure = (Spending % ÷ 100) × Total Earnings

Calculations:

⇒ Expenditure = (65 ÷ 100) × 720

⇒ Expenditure = 0.65 × 720 = ₹ 468

⇒ Savings = 720 − 468

⇒ Savings = ₹ 252

∴ The correct answer is ₹ 252.

Additional Information

Percentage Change

Percentage change = (New Value − Old Value) ÷ Old Value × 100. It measures the relative increase or decrease.

Complementary Percentages

If an entity is divided into two parts, the sum of their percentages always equals 100%. If spending is x%, savings must be (100 − x)%.

Base Value Concept

In percentage calculations, the total amount (Earnings) always acts as the base (100%) for calculating subsets like savings or expenses.

Question 89

Which of the following options should come in place of the question mark (?) in the given series based on the English alphabetical order?

GIN, JLQ, MOT, PRW, ?

  1. AOption (a)

    ZUS

  2. BOption (b)

    SZU

  3. COption (c)

    ZSU

  4. DOption (d)

    SUZ

View answer & explanation

Correct answer

Answer: (d)D.

SUZ

Why this answer is correct

The logic followed here is:

Logic: + 3 in each letter.

Hence, the correct answer is "Option 4".

Question 90

Seven people, A, B, D, L, X, Y and Z, are sitting in a row, facing north. Only five people sit between B and L. Z sits to the immediate left of L. Only one person sits between Z and D. A sits at some place to the left of Y but at some place to the right of X. Who sits third from the left end of the row?

  1. AOption (a)

    D

  2. BOption (b)

    X

  3. COption (c)

    Y

  4. DOption (d)

    A

View answer & explanation

Correct answer

Answer: (d)D.

A

Why this answer is correct

Given: Seven people, A, B, D, L, X, Y and Z, are sitting in a row, facing north.

Only five people sit between B and L.

Z sits to the immediate left of L. Only one person sits between Z and D.

 A sits at some place to the left of Y but at some place to the right of X.

Thus, A is the third from the left end of the row.

Hence, the correct answer is "Option 4".

Question 91

In a certain code language,

A + B means 'A is the wife of B',

A - B means 'A is the brother of B',

A × B means 'A is the father of B',

and A ÷ B means ‘A is the sister of B'.

How is P related to T if 'P + Q - R × S ÷ T'?

  1. AOption (a)

    Father's sister

  2. BOption (b)

    Father's brother's wife

  3. COption (c)

    Mother's brother's wife

  4. DOption (d)

    Mother

View answer & explanation

Correct answer

Answer: (b)B.

Father's brother's wife

Why this answer is correct

Given: 'P + Q - R × S ÷ T'

Decoded the symbols:

Alphabets+-*÷
Coded asWifeBrotherFatherSister

 'P + Q - R × S ÷ T' → It means that P is the wife of Q, Q is the brother of R, R is the father of S, S is the sister of T.

Thus, P is the Father's brother's wife of T.

Hence, the correct answer is "Option 2".

Question 92

The sum of the squares of the sides of a rhombus is 1600 cm2. What is the perimeter of the rhombus?

  1. AOption (a)

    20 cm

  2. BOption (b)

    40 cm

  3. COption (c)

    80 cm

  4. DOption (d)

    60 cm

View answer & explanation

Correct answer

Answer: (c)C.

80 cm

Why this answer is correct

Shortcut Trick

In a rhombus, all four sides (a) are equal.

Sum of squares of sides = 4a2 = 1600 cm2.

a2 = 400 → a = 20 cm.

Perimeter = 4a = 4 × 20 = 80 cm.

∴ The correct answer is 80 cm.

Alternate Method

Given: Sum of the squares of the sides of a rhombus = 1600 cm2.

Formula Used: Perimeter of Rhombus = 4 × side

Let the side of the rhombus be a.

⇒ Sum of squares of sides = a2 + a2 + a2 + a2 = 4a2

⇒ 4a2 = 1600

⇒ a2 = 1600 ÷ 4

⇒ a2 = 400

⇒ a = √400 = 20 cm

⇒ Perimeter = 4 × a

⇒ Perimeter = 4 × 20 = 80 cm

∴ The correct answer is 80 cm.

Additional Information

Relationship with Diagonals

The sum of the squares of the sides of a rhombus is equal to the sum of the squares of its diagonals: 4a2 = d12 + d22.

Area of Rhombus

The area of a rhombus can be calculated using diagonals: Area = (1/2) × d1 × d2.

Diagonals Property

The diagonals of a rhombus bisect each other at right angles (90°).

Question 93

As per the Hurun India rich list 2024, who replaced Reliance Industries chairman Mukesh Ambani?

  1. AOption (a)

    Nikesh Arora

  2. BOption (b)

    Gautam Adani

  3. COption (c)

    Nithin Kamath

  4. DOption (d)

    Jayshree Ullal

View answer & explanation

Correct answer

Answer: (b)B.

Gautam Adani

Why this answer is correct

The correct answer is Gautam Adani.

Key Points

  • Gautam Adani, the chairman of the Adani Group, has surpassed Mukesh Ambani in the Hurun India Rich List 2024.
  • The Adani Group is a diversified conglomerate with interests in ports, energy, and logistics, among other sectors.
  • Gautam Adani's net worth saw a significant increase, primarily driven by the performance of Adani Group companies in the stock market.
  • This marks a significant shift in the rankings of India's wealthiest individuals, with Adani Group's rapid expansion contributing to Gautam Adani's rise.
  • Gautam Adani's net worth is now estimated to be significantly higher than Mukesh Ambani's, reflecting the changing dynamics of wealth accumulation in India.

Additional Information

  • Adani Group
  • The Adani Group, founded by Gautam Adani in 1988, is one of India's largest business conglomerates.
  • It operates in various sectors including energy, resources, logistics, agribusiness, real estate, financial services, and defense.
  • The group is known for its significant investments in infrastructure and development projects across India and abroad.
  • Hurun India Rich List
  • The Hurun India Rich List is an annual ranking of the wealthiest individuals in India.
  • It is compiled by the Hurun Report, a leading research and luxury publishing group based in Shanghai.
  • The list provides insights into the wealth and financial status of India's richest individuals and families.
  • Mukesh Ambani
  • Mukesh Ambani is the chairman and largest shareholder of Reliance Industries, one of India's largest conglomerates.
  • He has consistently been one of the richest individuals in India and the world, largely due to the success of Reliance Industries.
  • Reliance Industries operates in sectors such as petrochemicals, refining, oil, telecommunications, and retail.

Question 94

Which of the following statements is/are correct related to transportation?

(i) Arteries are the vessels which carry blood away from the heart to various organs of the body.

(ii) The arteries have thin and elastic walls.

(iii) Veins have valves that ensure that blood flows only in one direction.

  1. AOption (a)

    Only (i) and (iii)

  2. BOption (b)

    Only (i) and (ii)

  3. COption (c)

    (i), (ii) and (iii)

  4. DOption (d)

    Only (i)

View answer & explanation

Correct answer

Answer: (a)A.

Only (i) and (iii)

Why this answer is correct

The correct answer is Only (i) and (iii).

Key Points

  • Arteries are the blood vessels that carry blood away from the heart to various organs of the body, ensuring oxygenated blood reaches tissues.
  • Veins have valves that ensure blood flows in one direction, preventing backflow and aiding in returning blood to the heart.
  • Arteries typically have thick and elastic walls to withstand high pressure from the pumping heart, contrary to the statement that they have thin walls.

Additional Information

  • Capillaries: These are the smallest blood vessels where the exchange of water, oxygen, carbon dioxide, and many other nutrients and waste substances occurs between blood and the tissues.
  • Circulatory System: Comprises the heart, blood, and blood vessels, responsible for transporting nutrients, oxygen, and hormones to cells and removing waste products.
  • Blood Pressure: The force exerted by circulating blood on the walls of blood vessels; arteries experience higher pressure compared to veins.
  • Oxygenated and Deoxygenated Blood: Arteries (except pulmonary arteries) carry oxygenated blood, while veins (except pulmonary veins) carry deoxygenated blood back to the heart.

Question 95

If 'A' stands for '-', 'B' stands for '×', 'C' stands for '÷' and 'D' stands for '+', what will come in place of the question mark '?' in the following equation?

23 D 18 C 3 B 5 A 17 = ?

  1. AOption (a)

    46

  2. BOption (b)

    56

  3. COption (c)

    36

  4. DOption (d)

    26

View answer & explanation

Correct answer

Answer: (c)C.

36

Why this answer is correct

Given: 23 D 18 C 3 B 5 A 17 = ?

Decoding the signs:

LettersABCD
Coded as-×÷+

23 D 18 C 3 B 5 A 17 = ?

⇒ 23 + 18 ÷  3 ×  5 - 17 = ?

​⇒ 23 + 30 - 17 = ?

​⇒ 53 - 17 = 36.

Hence, the correct answer is "Option 3".

Question 96

Which of the following statements is correct related to male reproductive system?

  1. AOption (a)

    Sperm formation requires higher temperature than the normal body temperature.

  2. BOption (b)

    Testes are located in the abdominal cavity.

  3. COption (c)

    Testes secrete testosterone hormone.

  4. DOption (d)

    Formation of sperm takes place in seminal vessel.

View answer & explanation

Correct answer

Answer: (c)C.

Testes secrete testosterone hormone.

Why this answer is correct

The correct answer is Testes secrete testosterone hormone..

Key Points

  • The testes are the primary male reproductive organs responsible for the production of sperm and testosterone.
  • Testosterone is the main male sex hormone that plays a key role in the development of male reproductive tissues and secondary sexual characteristics.
  • The hormone is crucial for the regulation of libido, bone mass, fat distribution, muscle mass, and the production of red blood cells and sperm.
  • Testosterone secretion is controlled by the hypothalamic-pituitary-gonadal axis, involving hormones such as GnRH, LH, and FSH.

Additional Information

  • Scrotum
  • The scrotum is a sac-like structure that houses the testes and regulates their temperature, keeping them cooler than the core body temperature, which is essential for optimal sperm production.
  • Spermatogenesis
  • Spermatogenesis is the process of sperm cell development, which occurs in the seminiferous tubules of the testes and involves the transformation of spermatogonia into mature spermatozoa.
  • Seminal Vesicles
  • Seminal vesicles are glands that secrete a significant portion of the fluid that becomes part of semen, providing nutrients and energy for sperm cells.
  • Hypothalamic-Pituitary-Gonadal Axis
  • This axis is a hormonal control system involving the hypothalamus, pituitary gland, and gonads, which regulates reproductive function and hormone production in both males and females.
  • Androgens
  • Androgens are a group of hormones that include testosterone, which are responsible for the development and maintenance of male characteristics.

Question 97

If the diameter and the height of a cylinder are 10 cm and 10.5 cm, respectively, then using π = 227\frac{22}{7}, find the volume of the cylinder.

  1. AOption (a)

    985 cm3

  2. BOption (b)

    785 cm3

  3. COption (c)

    888 cm3

  4. DOption (d)

    825 cm3

View answer & explanation

Correct answer

Answer: (d)D.

825 cm3

Why this answer is correct

Shortcut Trick

Volume of a cylinder = π × r2 × h

Given Diameter = 10 cm ⇒ Radius (r) = 5 cm

Height (h) = 10.5 cm

Volume = (22/7) × 5 × 5 × 10.5 = 22 × 25 × 1.5 = 825 cm3

∴ The correct answer is 825 cm3.

Alternate Method

Given:

Diameter (d) = 10 cm

Height (h) = 10.5 cm

Formula Used:

Volume = πr2h, where r = d/2

Calculations:

⇒ Radius (r) = 10 ÷ 2 = 5 cm

⇒ Volume = (22/7) × (5)2 × 10.5

⇒ Volume = (22/7) × 25 × (21/2)

⇒ Volume = 11 × 25 × 3

⇒ Volume = 11 × 75

⇒ Volume = 825 cm3

∴ The correct answer is 825 cm3.

Additional Information

Curved Surface Area (CSA) of Cylinder

The area of the curved surface is given by the formula: CSA = 2πrh.

Total Surface Area (TSA) of Cylinder

The total area including the two circular bases: TSA = 2πr(h + r).

Volume of a Hollow Cylinder

If R is outer radius and r is inner radius: Volume = πh(R2 − r2).

Question 98

In the following number-pairs, the second number is obtained by applying certain mathematical operations to the first number. Which numbers should replace X and Y so that the pattern followed by the two numbers on the left side of ∶∶ is the same as that on the right side of ∶∶?

(NOTE: Operations should be performed on the whole numbers, without breaking down the numbers into its constituent digits. E.g. 13 - Operations on 13 such as adding/subtracting/multiplying etc. to 13 can be performed. Breaking down 13 into 1 and 3 and then performing mathematical operations on 1 and 3 is not allowed.)

X ∶ 87 ∶∶ 14 ∶ Y

  1. AOption (a)

    X = 8, Y = 154

  2. BOption (b)

    X = 9, Y = 153

  3. COption (c)

    X = 8, Y = 153

  4. DOption (d)

    X = 9, Y = 155

View answer & explanation

Correct answer

Answer: (c)C.

X = 8, Y = 153

Why this answer is correct

The logic followed here is:

Logic: (1st number × 11) - 1 = 2nd number.

For, X ∶ 87

⇒ (X × 11) - 1 = 87

⇒ (X × 11) = 87 + 1

⇒ (X × 11) = 88

⇒ X = 88 ÷ 11 = 8.

Similarly,

14 ∶ Y

⇒ (14 × 11) - 1 = Y

⇒ 154 - 1 = Y.

⇒ 153.

Thus, X = 8, Y = 153

Hence, the correct answer is "Option 3".

Question 99

Which of the following transports food, carbon dioxide and nitrogenous wastes in a dissolved form?

  1. AOption (a)

    Plasma

  2. BOption (b)

    Blood platelets

  3. COption (c)

    Lymph

  4. DOption (d)

    Red blood corpuscles

View answer & explanation

Correct answer

Answer: (a)A.

Plasma

Why this answer is correct

The correct answer is Plasma.

Key Points

  • Plasma is the liquid component of blood that transports nutrients, hormones, and proteins to the parts of the body that need it.
  • It makes up about 55% of the body's total blood volume.
  • Plasma carries carbon dioxide, which is a waste product of cellular metabolism, from tissues to the lungs for exhalation.
  • It also transports nitrogenous wastes to the kidneys for excretion.
  • Plasma helps maintain blood pressure and regulates body temperature.

Additional Information

  • Blood Composition
  • Blood consists of cells suspended in plasma: red blood cells (RBCs), white blood cells (WBCs), and platelets.
  • RBCs are responsible for oxygen transport, WBCs are involved in immune response, and platelets play a key role in blood clotting.
  • Functions of Plasma
  • Plasma serves as a medium for transporting nutrients, waste products, and other substances throughout the body.
  • It contains clotting factors that help prevent excessive bleeding during injury.
  • Plasma proteins, like albumin, help maintain osmotic balance and transport hormones, vitamins, and drugs.
  • Carbon Dioxide Transport
  • Carbon dioxide is primarily transported in the blood in the form of bicarbonate ions (HCO3-).
  • A smaller amount is dissolved directly in plasma, and some bind to hemoglobin in red blood cells.
  • Nitrogenous Wastes
  • Nitrogenous wastes like urea and creatinine are byproducts of protein metabolism.
  • These wastes are carried by plasma to the kidneys, where they are filtered out and excreted in urine.

Question 100

Silver ornaments become black after some time because silver reacts with ______ present in the air.

  1. AOption (a)

    nitrogen

  2. BOption (b)

    carbon dioxide

  3. COption (c)

    sulphur

  4. DOption (d)

    oxygen

View answer & explanation

Correct answer

Answer: (c)C.

sulphur

Why this answer is correct

The correct answer is sulphur.

Key Points

  • Silver ornaments tarnish and turn black due to the formation of silver sulphide (Ag2S).
  • This reaction occurs when silver comes into contact with hydrogen sulphide (H2S) present in the air.
  • The chemical reaction is: 4Ag + 2H2S + O2 → 2Ag2S + 2H2O.
  • Hydrogen sulphide is often found in polluted air, emitted from sources like sewage, swamps, and industrial processes.

Additional Information

  • Silver Tarnishing
  • Tarnishing is a surface discoloration on silver, a result of the metal reacting with sulphur compounds in the air.
  • Tarnish is essentially corrosion that affects only the outer layers of the metal.
  • Hydrogen Sulphide (H2S)
  • It is a colorless gas with a characteristic odor of rotten eggs.
  • It is produced naturally by the decomposition of organic matter and is also a by-product of industrial activities.
  • Preventing Tarnish
  • Storing silver in airtight containers can reduce exposure to air and pollutants.
  • Using anti-tarnish strips or bags can also help in preventing tarnish.
  • Cleansing Tarnished Silver
  • Tarnished silver can be cleaned using silver polish or homemade remedies like baking soda and vinegar.
  • A common method involves placing silver in aluminum foil and soaking it in a solution of baking soda and hot water.

100 questions in the full paper