Q. A body of mass $5\ kg$ moving with a velocity $10\ m/s$ collides with another body of the mass $20\ kg$ at, rest and comes to rest. The velocity of the second body due to collision is
A) $2.5\ m/s$
B) $5\ m/s$
C) $7.5\ m/s$
D) $10\ m/s$
Explanation
(a) Momentum conservation
$5 \times 10 + 20 \times 0 = 5 \times 0 + 20 \times v \Rightarrow v = 2.5\ m/s$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.