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

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 initialy at rest. The fraction of K.E. lost by colliding particle is
Answer» `1//3` `1//9` `8//9` `2//3` ANSWER :C