JEE Main20198 Apr 2019Evening ShiftPhysicsCenter of Mass, Momentum and CollisionActual
A body of mass m 1 moving with an unknown velocity of v 1 i ^ , undergoes a collinear collision with a body of mass m 2 moving with a velocity v 2 i ^ . After the collision, m 1 and m 2 move with velocities of v 3 i ^ and v 4 i ^ , respectively. If m 2 = 0.5 m 1 and v 3 = 0.5 v 1 , then v 1 is:
Options
- Av 4 - v 2 4
- Bv 4 - v 2 2
- Cv 4 + v 2
- Dv 4 - v 2
Correct answer
D. v 4 - v 2
Step-by-step solution
From the conservation of linear momentum, m 1 v 1 + m 2 v 2 = m 1 v 3 + m 2 v 4 m 1 v 1 + 0.5   m 1   v 2 = m 1 0.5   v 1 + 0.5   m 1   v 4 0.5   v 1 + 0 . 5   v 2 = 0.5   v 4 v 4 = v 1 + v 2 v 1 = v 4 - v 2