Question

a ball of mass m is thrown at an angle 45 to the horizontal with speed v from the ground. the change in kinetic energy when it returns to the ground is

Answer 1

kinetic energy is a scaler quantity and depends on speed since the speed with which the ball was thrown is equal to the speed with which it hits the ground

Change in KE = 0

Answer 2

Explanation:

change in KE is zero

since energy is conserves, KE+PE is constant

since potential energy depends on position, initial and final PE is same. Hence initial and final KE is same too..