Question 232: Centre of Mass and Rotational Motion

Question

A bomb of mass $16kg$ at rest explodes into two pieces of masses $4$ $kg$ and $12$ $kg.$ The velocity of the $12$ $kg$ mass is $4\,\,m{s^{ - 1}}.$ The kinetic energy of the other mass is

Accepted Answer

Here linear momentum is conserved as no external force is acting on the bomb.
Let the velocity and mass of $4$ $kg$ piece be ${v_1}$ and ${m_1}$ and that of $12$ $kg$ piece be ${v_2}$ and ${m_2}$.
Applying conservation of linear momentum
$0 = {m_2}{v_2} - {m_1}{v_1}$
$\Rightarrow {v_1} = {{12 	imes 14} \over 4} = 12\,m{s^{ - 1}}$
$	herefore$ $K.E{_1} = {1 \over 2}{m_1}v_1^2 = {1 \over 2} 	imes 4 	imes 144 = 288\,J$

Answer

$144$ $J$

Answer

$288$ $J$

Answer

$192$ $J$

Answer

$96$ $J$

Centre of Mass and Rotational Motion

A bomb of mass 16kg at rest explodes into two pieces of masses 4 kg and 12 kg. The velocity of the 12 kg mass is 4\,\,m{s^{ - 1}}. The kinetic energy of the other mass is

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