Highly selective Backlog Qs for JEE MainPhysicsCenter of Mass, Momentum and Collision
A 2 ~kg ball moving at 24 ~ms ⁻¹ undergoes inelastic head-on collision with a 4 ~kg ball moving in the opposite direction at 48 ~ms ⁻¹ . If the coefficient of restitution is 2 / 3 , their velocities in ms ⁻¹ after impact are
Options
- A-56,-8
- B-28,-4
- C-14,-2
- D-7,-1
Correct answer
A. -56,-8
Step-by-step solution
aligned & aligned & v₁^ = [ m₁-e m₂ m₁+m₂ ] v₁- [ (1+e) m₂ m₁+m₂ ] v₂ &= [ 2- ( 2 3 ) 4 2+4 ] 24- [ (1+ 2 3 ) 4 2+4 ] 48 &=-56 ~m / s & and v₂^ = [ (1+e) m₁ m₁+m₂ ] v₁- [ m₂-e m₁ m₁+m₂ ] v₂ &= [ (1+ 2 3 ) 2 2+4 ] 24- [ 4- ( 2 3 ) 2 2+4 ] 48 &=-8 ~m / s aligned aligned