A bomb of 12 kg explodes into two pieces of masses 4 kg and 8 kg . The velocity of 8 kg mass is 6 m / sec . The kinetic energy of the other mass is

Options

A. 24 J
B. 32 J
C. 128 J
D. 288 J

Answer

D

Explanation

`8 xx 6 + 4 V = 0`
or `" " V = - (48)/(4) = - 12 ` m/s
`therefore ` Kinetic energy = `(1)/(2) mv^(2)`
= `(1)/(2) xx 4 xx (-12)^(2)`
= 288 J