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Concept**:**

• Power (P): The rate of work done is called power. 
• The SI unit of power is the watt (W).
• Power is also measured in Kilowatt (kW).
• Horsepower**:** The unit of measurement of power or the rate at which work is done is called Horsepower.
• 1 horsepower = 746 W = 0.746 kW. So option 4 is correct.

CONCEPT:

• Pseudo forces: It is basically an unreal force, which is not actually applied to anybody but yet the body feels it.
• Pseudo force is acted on a body due to acceleration i.e., the non-inertial frame of reference, hence Newton's law is not valid for such force.
• For example, You all must have experienced that, when you sit in your car which is at rest initially and then if the car starts moving suddenly, you experience a backward push.
• These pushes are not really applied by any physical object on you, yet you experience it every time. So these types of force are known as pseudo force.

Explanation:

From the above explanation, we can see that pseudo force is the cause because of the accelerating frame of reference or non-inertial frame and we know that newton law of motion is not valid for the non-inertial frame of reference.

Hence pseudo force does not obey newton's law of motion.

Extra point:

• Frame of reference: If we are observing any moving body or anybody at rest with respect to any moving object or from any object at rest then the object is called frame of reference.

There are two types of frame of reference:

• Inertial frame of reference: The frame of reference having zero acceleration is called Inertial frame of reference.
• This frame of reference will be either in rest or will be moving with a constant velocity.
• The newton’s law is valid in this frame of reference.
• Non-inertial frame of reference: The frame of reference having non-zero acceleration is called the non-inertial frame of reference.
• The newton’s law is not valid in this frame of reference.
• For example: If we are observing an object from a freely falling object then this will be a non-inertial frame of reference because the freely falling body has some acceleration.

The below table shows the difference between real and pseudo force

The correct answer is Barometer.

Key Points

• A barometer is an instrument used to measure atmospheric pressure.
• It is essential in weather forecasting and determining altitude.
• Barometers come in two main types: mercury barometers and aneroid barometers.
• Mercury barometers use mercury in a glass tube, while aneroid barometers use a small, flexible metal box called an aneroid cell.

Additional Information

• Atmospheric Pressure
• It is the force exerted onto a surface by the weight of the air above that surface in the atmosphere of Earth (or that of another planet).
• It is measured in units such as Pascals (Pa), millibars (mb), or inches of mercury (inHg).
• Mercury Barometer
• Invented by Evangelista Torricelli in 1643.
• Consists of a long glass tube filled with mercury, with one end open to the atmosphere.
• Aneroid Barometer
• Does not use liquid; instead, it uses a small, flexible metal box (aneroid cell).
• The cell expands or contracts with changes in atmospheric pressure, and this movement drives a mechanical pointer on a dial.
• Uses of Barometers
• Weather forecasting by measuring atmospheric pressure changes to predict short-term changes in the weather.
• Altitude determination, as atmospheric pressure decreases with an increase in altitude.

The correct answer is 12 u.

Key Points

• Carbon-12 is the most common isotope of carbon, consisting of 6 protons and 6 neutrons.
• The atomic mass unit (u) is a standard unit of mass that quantifies mass on an atomic or molecular scale (atomic mass).
• The atomic mass of an atom is defined relative to the atomic mass of Carbon-12, which is set at 12 u.
• This standardization helps in comparing the masses of different atoms.
• The mass of Carbon-12 is exactly 12 u because it is the reference from which atomic masses are calculated.

 Additional Information

• 14 u
• This value is closer to the atomic mass of the isotope Carbon-14, which has 6 protons and 8 neutrons.
• Carbon-14 is used in radiocarbon dating to determine the age of ancient objects.
• 6 u
• This is incorrect as it does not match the atomic mass of any naturally occurring carbon isotope.
• 16 u
• This value is closer to the atomic mass of the isotope Oxygen-16, which has 8 protons and 8 neutrons.
• Oxygen-16 is the most abundant isotope of oxygen.

The correct answer is Candela.

Key Points

• Fundamental units: The fundamental units are those units that are derived from fundamental quantities, as they can describe by the(SI unit) International unit.
• They are basically not dependent on any other units, and all other units are created and derived from them. 

There are 7 fundamental units that are present in nature.

• which are as follows-

Additional Information

• From the above table, we can say that
• Mole is the SI unit of the amount of substance. So option 1 does not follow.
• Candela is the SI unit of luminous intensity. So option 2 follows.
• Kelvin is the SI unit of temperature. So option 3 does not follow.
• Ampere is the SI unit of electric current. So option 4 does not follow.

The logic here is as follows:

356 : 21 → 356 : 3 × 5 + 6 = 21

Similarly,

269 : ? → 269 : 2 × 6 + 9 = 21

Hence, the correct answer is 21.

Preparing the family tree using the following symbols:

A possible family tree diagram will be:

Therefore, T is the mother of M.

Hence, the correct answer is "Mother".

The logic followed here is:

Logic: 1^st Number × 11 + 8 = 2^nd Number

• 9 : 107 → 9 × 11 + 8 = 99 + 8 = 107

Similarly,

• 8 : ? → 8 × 11 + 8 = 88 + 8 = 96

Hence, '96' is the correct answer.

The logic follows here is;

Hence, "180" is the correct answer.

BODMAS Table: 

Given equation: 109 - 55 × 605 ÷ 77 + 93 = ?

Now, if ‘+’ and ‘-‘ and ‘×' and '÷’ are interchanged, then:

⇒ 109 + 55 ÷ 605 × 77 - 93 = ?

⇒ 109 + \({55 \times 77\over 605}\) - 93 = ?

⇒ 109 + 7 - 93 = ?

⇒ 116 - 93 = 23.

Hence, the correct answer is "Option 2".