Question

State the law of conservation of momentum. Why is a person hit harder when he falls on a hard floor than when he falls on sand from the same height? A bullet of mass 20g is fired horizontally with a velocity 100ms⁻¹ from a pistol of mass 1.5 kg. Calculate the recoil velocity of the pistol.

An object of mass 20 kg is sliding with a constant velocity of 4 m/s on a frictionless horizontal surface. The force required to keep the object moving with the same velocity is-

Attempt either (I) with all sub parts or (II) with all sub parts from the following two questions-

Assertion (A): It is difficult to push or pull a heavy box over the ground. Reason (R): Heavy objects have more inertia.