Question

A shell of mass `20 kg` at rest explodes into two fragments whose masses are in the ratio `2 : 3`. The smaller fragment moves with a velocity of `6 m//s`. The kinetic energy of the larger fragment is
A. `96 J`
B. `216 J`
C. `144 J`
D. `360 J`

Answer 1

Correct Answer - A
By the momentum conservation
`0 = 2m xx 6 - 3 mv`
`rArr v = 4 m//s`
` (1)/(2) xx 3 xx v^(2) = (1)/(2) (3 xx 4) (4)^(2) = 96 J`