Q. A stationary bomb explodes into three pieces. One piece of 2 kg mass moves with a velocity of ${8\ ms}^{- 1}$at right angles to the other pieces of mass 1 kg moving with a velocity of ${12\ \ ms}^{- 1}$. If the mass of the third piece is 0.5 kg, then its velocity is
A) ${10\ ms}^{- 1}$
B) ${20\ ms}^{- 1}$
C) ${30\ ms}^{- 1}$
D) ${40\ ms}^{- 1}$
Explanation
(d) Momentum of the piece
$p = \sqrt{p_{x}^{2} + p_{y}^{2}}$
$= \sqrt{(16)^{2} + (12)^{2}}$
$= 20$
$v = \frac{p}{m} = \frac{20}{0.5} = 40\ m/s$
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Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.