A moving particle of mass .m. makes head-on elastic collision with a particle of mass 2m. which is initially at rest. What is the fraction of K.E. lost by colliding particle ?

A moving particle of mass .m. makes head-on elastic collision with a p

1.	A moving particle of mass .m. makes head-on elastic collision with a particle of mass 2m. which is initially at rest. What is the fraction of K.E. lost by colliding particle ?
Answer» ANSWER :`8//9`