Question

What will be the magnitude of change in momentum imparted by the floor to a ball of mass 1kg if it falls from the height of 100 cm on the floor and rebound vertically upward with same speed? (g=10 meters per second square)?

Answer 1

Velocity of the ball when hitting the floor
= √2*g*h = √ 2*10*1 = √20 m/s

So,
Initlal momentum= -mv = -√20 kgm/s

Final momentum = +mv = √20 kgm/s

Net change in momentum = mv - (-mv)
= 2 mv = 2*√20 kg m/s
= 4√5 kg m/s