KCET2016PhysicsCenter of Mass, Momentum and Collision
A ( 12 ~kg ) bomb at rest explodes into two pieces of ( 4 ~kg ) and ( 8 ~kg ). If the momentum of ( 4 ~kg ) piece is ( 20 Ns ), the kinetic energy of the ( 8 ~kg ) piece is
Options
- A( 25 ~J )
- B( 20 ~J )
- C( 50 ~J )
- D(40 J
Correct answer
A. ( 25 ~J )
Step-by-step solution
Given, mass of bomb, M=12 ~kg ; m₁=4 ~kg , m₂=8 ~kg momentum of m₁=p₁=20 ~N Now given, p₁=20 ~N , momentum of 8 ~kg piece p₂=20 ~N Thus, kinetic energy of 8 ~kg piece is 1 2 p² m₂ = 1 2 20 20 8 = 100 4 =25 ~J