Question

A ball of mass 1 kg is dropped from 20m height on ground and it rebounds to height 5m.Find the magnitude of change in momentum during its collision

Answer 1

for downward motion ;

u=0 m/s

a=10 m/s2

s=20 m

using v2- u2=2as

v= 20m/s

for upward motion;

v=0 m/s

a=10 m/s2

s=5 m using v2 – u2=2as

u= -10 m/s

I=mv – mu

I=20+10=30 kg m/s