Q. A bomb of mass 9 kg explodes into two parts. One part of mass 3 kg moves with velocity 16 m/s ,then the KE of the other part is
A) 162 J
B) 150 J
C) 192 J
D) 200 J
Explanation
(c) From the law of conservation of momentum
$\ 3 \times 16 + 6 \times v = 9 \times 0$
Or $v = - 8\ ms^{- 1}$
$\Rightarrow \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ v = 8ms^{- 1}\ (numerically)$
Therefore, its kinetic energy
$k = \frac{1}{2} \times 6 \times (8)^{2} = 192J$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.