Answer:
In an elastic collision:
- There is no external net force acting. Thus, Momentum before and after collision is equal. Momentum remains conserved.
- Total energy always remains conserved as energy cannot be created nor destroyed. It can change from one form to another.
- There is no lost due to friction in elastic collision. So the kinetic energy is also conserved.
- Velocities may change after collision. If the masses are equal, the velocities interchange.
When one object is stationary:
Final velocity of object 1:
v₁ = (m₁ - m₂)u₁/(m₁ +m₂)
Final velocity of object 2:
v₂ = (2 m₁ u₁)/(m₁+m₂) =
- Objects do not stick together in elastic collision. They stick together in inelastic collision.
- One object may be stationary before the elastic collision.
Thus, conditions for an elastic collision:
- Energy is conserved.
- Velocities may change.
- Momentum is conserved.
- Kinetic energy is conserved.
- One object may be stationary before the elastic collision.
