A bomb of mass 9 kg explodes into 2 pieces

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A bomb of mass $9\,kg$ explodes into $2$ pieces of mass $3\,kg$ and $6\,kg.$ The velocity of mass $3\,kg$ is $1.6\, m/s$, the K.E. of mass $6\,kg$ is ............ $J$

A

$3.84$

B

$9.6$

C

$1.92$

D

$2.92$

A bomb of mass $9\,kg$ explodes into $2$ pieces of mass $3\,kg$ and $6\,kg.$ The velocity of mass $3\,kg$ is $1.6\, m/s$, the K.E. of mass $6\,kg$ is ............ $J$

As the bomb initially was at rest therefore
Initial momentum of bomb $= 0$
Final momentum of system = ${m_1}{v_1} + {m_2}{v_2}$
As there is no external force
 ${m_1}{v_1} + {m_2}{v_2} = 0$ ==> $3 \times 1.6 + 6 \times {v_2} = 0$
velocity of 6 kg mass ${v_2} = 0.8\,m/s$ (numerically)
Its kinetic energy$ = \frac{1}{2}{m_2}v_2^2$$ = \frac{1}{2} \times 6 \times {(0.8)^2} = 1.92\,J$