A bomb of mass 3.0Kg explodes in air into two pieces of masses 2.0 kg and 1.0 kg . The smaller mass goes at a speed of 80 m/s .The total energy imparted to the two fragments is

Options

A. 1.07 kJ
B. 2.14 kJ
C. 2.4 kJ
D. 4.8kJ

Answer

D

Explanation

Both fragment will possess the equal linear momentum
`m_(1)v_(1)=m_(2)v_(2)rArr 1xx80=2xx v_(2)rArr v_(2)=40 m//s`
`therefore` Total energy of system `=(1)/(2)m_(1)v_(1)^(2)+(1)/(2)m_(2)v_(2)^(2)`
`=(1)/(2)xx1xx(80)^(2)+(1)/(2)xx2xx(40)^(2)`
`= 4800 J = 4.8 kJ`