Q.

A moving particle of mass m, makes a head on elastic collision with another particle of mass 2m, which is initially at rest. The percentage loss in energy of the colliding particle on collision, is close to ..........


Ans.

(89)

Fractional decrease in kinetic energy of mass 'm'

=1-(m2-m1m2+m1)2=1-(2-12+1)2=1-(13)2=1-19=89

Percentage loss in energy =89×100≈89%