Objective Type Questions on Class 11 Physics Chapter 5 Laws of Motion

1 Which of the following should be constant for a body to have a constant momentum?

A Acceleration

B Force

C Velocity

D All of the above

Answer:All of the above

2 Consider a man standing on the spring balance such that the reading on the spring balance is 60kg. If the man jumps out of the spring balance what will be the final reading of the spring balance?

A Remains unchanged

B Increases

C Decreases

D First increases then decrease to zero

View Answer

Answer:First increases then decrease to zero

3 What is the force acting on the particle if the motion of the particle is given as

A F = ma

B F = 0

C F = mg

D F ≠ 0

View Answer

Answer:F = mg

4 Let two bodies be with masses 2kg and 5kg respectively. Let these bodies be at rest with the same force acting on them. Calculate the ratio of times that is required by both the bodies to reach the final velocity.

A 2:5

B 25:4

C 5:3

D 4:25

View Answer

Answer:2:5

5 Consider a car that overturns while taking a turn. Select the option that is experienced by the wheels of the car.

A First, both inner, as well as the outer wheel, leave the ground

B First, the inner wheel leaves the ground

C The inner wheel experiences no change

D None of the above

View Answer

Answer:First, the inner wheel leaves the ground

6 Choose the correct statement

A A body can be accelerated by frictional force

B There can be zero friction

C Kinetic friction is greater than rolling friction

D Frictional force and area of contact between the two surfaces are proportional

View Answer

Answer:Kinetic friction is greater than rolling friction

7 A particle of mass m is given an impulse such that the velocity of the particle changes from v1 to v2. The impulse is equal to

A m(v₂ + v₁)

B m (v₂ – v₁)

C m (|v₂|-|v₁|)

D 1/2(v 2/2−v 2/1)

View Answer

Answer:m (v₂ – v₁)

8 What is the condition required to move the block without slipping

A μB/μm > M/m

B μB/μm > m/M

C μB/μm < M/m

D μB/μm < m/M

View Answer

Answer:μB/μm > M/m

9 What maximum force boy can apply without slipping

A μ_mmg

B μ_mMg

C μ_Bmg

D none of the above

View Answer

Answer:μ_Bmg

10 Which of the following expression is correct if at t = 0, object is at origin and velocity is v₀ = i + j

A r = i(2.5 t² + t) + j(t - 1.5t²)

B r = i(2.5 t² - t) + j(t + 1.5t²)

C r = it - jt2

D none of the above

View Answer

Answer:r = i(2.5 t² + t) + j(t - 1.5t²)

11 find the acceleration of object

A 5i + 3j

B 5i - 3j

C 3i + 5j

D 3i - 5j

View Answer

Answer:5i - 3j

12 Find the velocity as a function of distance

A v₀ + kx/m

B v₀ - kx/m

C v₀ - x/m

D none of the above

View Answer

Answer:v₀ - kx/m

13 Find the value of x at which it velocity become 0

A mv₀/k

B mv₀/k₂

C m/kv₀

D none of the above

View Answer

Answer:mv₀/k

14 Find the velocity of body as a function of time

A v₀ exp (-kt/m)

B v₀ exp (-mt/k)

C v₀ exp (-t)

D none of the above

View Answer

Answer:v₀ exp (-kt/m)

15 A block of mass M is kept on a friction floor of static friction μ. The body is acted by a horizontal force F horizontally but the body does not move. Now an another f act on the body vertically downwards, what will happen

A frictional force on the block is change

B normal reaction on the block change

C limiting frictional force changes

D body starts moving

View Answer

Answer:B, C

16 Consider the figure given below

Laws of Motion

if Coefficient of friction is μ then what is the least value of μ so the system remains at rest

A 0.23

B 0.2

C 0.203

D 0.13

View Answer

Answer:0.203

17 A particle of mass M, originally at rest is subjected to a force whose direction is constant but whose magnitude varies with the time according to the relation

Laws of motion