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B. Newton’s second law of motion.

C. Newton’s third law of motion.

D. Newton’s law of gravitation

Q.3 A particle of mass 4 kg is acted upon by steady force of 4 N. Distance travelled by the

particle in 4 sec is

A. 16 m

B. 2 m

C. 8 m

D. 4 m

Q.4 Assertion: Action and reaction cannot cancel each other.

Reason: Action and reaction act on different bodies.

Q.5 Assertion: Momentum is a scalar quantity

Reason: Change in momentum is produced by a force.

Q.6 A. Write Newton’s Second law of motion. Derive an expression for it.
B.A cricketer catches a ball of mass 150 g in 0.1 s moving with speed 20 m/s. Find the
magnitude of force experienced.

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Q.7 A. A car of mass 1000 kg travelling at 32 ms dashes into the rear of a truck of mass 8000 kg
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moving in the same direction with a velocity of 4 ms . After the collision, the car bounces
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with a velocity of 8 ms . What is the velocity of truck after the impact?

B.A 10g bullet is shot from a 5kg gun with a velocity of 400m/s. What is the recoil velocity of
gun?

Q.8 A.Derive the expression for conservation of linear momentum.
B. Give reason
i.When a man jumps out of a boat to the shore, the boat slightly moves away from the shore
ii. Why does the gun recoils when the bullet is fired from it.

Q.9 A. An army vehicle of mass 1000 kg is moving with a velocity of 10 m/s and is acted upon by
a forward force of 1000 N due to the engine and a retarding force of 500 N due to friction.
What will be its velocity after 10 s?

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B.A cricket ball of mass 150 g is moving with a velocity of 12 ms , and is hit by a bat, so that
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the ball is turned back with a velocity of 20 ms . The force of the blow acts for 0.01 second