Q. Two masses of $0.25\ kg$ each moves towards each other with speed $3ms^{- 1}$ and $1ms^{- 1}$ collide and stick together. Find the final velocity
A) $0.5\ ms^{- 1}$
B) $2ms^{- 1}$
C) $1ms^{- 1}$
D) $0.25\ ms^{- 1}$
Explanation
(c) [image:6_image63.emf]
Here, $m = 0.25\ kg,\ u_{1} = 3ms^{- 1},\ u_{2} = - 1ms^{- 1}$
It is an inelastic collision
According to conservation of momentum
$mu_{1} + mu_{2} = (m + m)v$
$\Rightarrow v = \frac{mu_{1} + mu_{2}}{2m} = \frac{u_{1} + u_{2}}{2} = \frac{3 - 1}{2} = 1ms^{- 1}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.