UNITS & MEASUREMENTS NEET PYQ ‘s & PRACTICE QUESTIONS

UNITS & MEASUREMENTS NEET PYQ ‘s

The dimension of a physical quantity are the powers to which the fundamental (or base) quantities like mass, length and time etc. have to be raised to represent the quantity. Consider the physical quantity “Force”. The unit of force is Newton.

1 Newton = 1 kg m/sec²

 kg → M¹ (Mass);  3 → L¹ (Length);  s-² → T^-2 (Time)

∴ Dimensions of force are [M¹L¹T^-2]

Dimensional formula for some Physical quantities

Mechanical equivalent of heat

Physical quantity	Relation with other quantity	Dimensional formula
Area	Length × breadth	L × L = [L2]
Density	Mass/volume
Acceleration
Force	F = ma	[MLT−2]
Linear momentum	P = mv	[MLT−1]
Pressure	P = F/A	[ML−1T−2]
Universal gravitational constant		[M−11L3T −2]
Work	W = F × d	[ML2T −2]
Energy (kinetic, potential and heat)	1/2 mv2	[ML2T −2]
Surface tension		[ML°T−2]

Strain		[M°L°T°]
Modulus of elasticity		[ML−1T−2]
Angle		[M°L°T°]
Coefficient of viscosity		[M1L−1T−1]
Planck ’s constant	h = mvλ	[ML2T−1]
Thermal resistance		[M −1L−2T3 θ]
Thermal conductivity		[MLT−3θ−1]
Boltzman’s constant	k = R/N	[ML2 T−2θ−1]
Universal gas constant		[ML2T−2 θ − 1]
J = W/H	[M°L°T°]
Decay constant		[M °L °T −1]

Question: The diameter of a spherical bob, when measured with vernier callipers yielded the following values :3.33 cm, 3.32 cm, 3.34 cm, 3.33 cm and 3.32 cm. The mean diameter to appropriate significant figures is: (NEET 2023 Manipur )

A 3.328 cm

B 3.3 cm

C 3.33 cm

D 3.32 cm

Answer: C

SOLUTION: 1

SOLUTION: 1

Question: The dimensional formula of magnetic flux is:

Solution: A

QUESTION: A pair of physical quantities having same dimensional formula is:

A. Force and Torque

B. Work and Energy

C. Force and Impulse

D. Linear momentum and angular momentum

SOLUTION: B

Question: Planck’s constant has the dimensions of:

A. Linear Momentum

B. Angular Momentum

C. Energy

D. Power

Solution: B

Question: The ratio of the dimensions of Planck’s constant and that of the moment of inertia is the dimension of:

A. Frequency

B. Velocity

C. Angular momentum

D. Time

Answer: A

QUESTION:

Answer: A

QUESTION: Dimensions of resistance in an electrical circuit, in terms of dimension of mass M, of length L, of time T and of current I, would be:

SOLUTION: D

QUESTION: If the error in the measurement of radius of a sphere is. 2%, then the error in the determination of volume of the sphere will be

A. 4%

B. 6%

C. 8%

D. 2%

SOLUTION: B

QUESTION:

Which two of the following five physical parameters have the same dimensions?          [AIPMT (S) 2008]

(1) energy density

(2) refractive index

(3) dielectric constant

(4) Young’s modulus

(5) magnetic field

Options: A. 2& 4

B. 3 & 5

C. 1& 4

D. 1 & 5

SOLUTION: C

QUESTION:

SOLUTION: D

QUESTION:

SOLUTION: A

QUESTION:

ANSWER: B

QUESTION:

SOLUTION: B

QUESTION:

SOLUTION: B

This expression for speed of light and the dimensions of speed of light are

QUESTION: A stone is dropped from a height h. It hits the ground with a certain momentum p. If the same stone is dropped from a height 100% more than the previous height, the momentum when it hits the ground will change by

A. 68%

B. 41%

C. 200%

D. 100%

SOLUTION: B

QUESTION:

SOLUTION: C

Also study: NEET QUIZ ON KINETICS

UNITS & MEASUREMENTS NEET PYQ