Laws of motion MCQs
1. 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|)
Answer: (b) m (v2 – v1)
2. 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
Answer: (c) Kinetic friction is greater than rolling friction
3. 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
Answer: (b) First, the inner wheel leaves the ground
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
Answer: (a) 2:5
5. 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
Answer: (d) First increases then decreases to zero
6.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: (d) All of the above
