How Does Kinetic Energy Transfer in a Perfectly Elastic Collision?

[stupif]

1.A 0.16kg ball makes an perfectly elastic head on collision with a second ball initially at rest. the second ball moves off with half the original speed of the first ball



2. what fraction of the origianl kinetic energy gets transferred to the second ball? answer=108J
i found out the mass of the second ball, 0.48kg
help me...please
thank you

The Attempt at a Solution

 

[PeterO]

1.A 0.16kg ball makes an perfectly elastic head on collision with a second ball initially at rest. the second ball moves off with half the original speed of the first ball



2. what fraction of the origianl kinetic energy gets transferred to the second ball? answer=108J
i found out the mass of the second ball, 0.48kg
help me...please
thank you

The Attempt at a Solution

You are aware that both momentum and kinetic energy are conserved in a "perfrectly elastic collision" aren't you. Do you also remember that momentum is a vector and Kinetic energy is scalar.