Question

A ball mass 2 kg moving with a velocity of 4 m/s hit another ball 5 kg at rest. calculate the velocity of the second ball if the velocity of the first ball after hitting becomes 2.5 m/s.​

Answer 1

Kinetic energy of 1st ball=1/2mv²

=1/2*2*4*4=16 J

Let the velocity 2nd wall =u

Thne afer hitting

KE1=KE2

1/2*2*2.5*2.5=1/2*5*u²

u²=2.5

u=√2.5 m/sec