There are three types of collision:
- Elastic: no kinetic energy is lost
- Inelastic: all kinetic energy is lost
- Partially inelastic: some kinetic energy is lost
The type can be determined by calculating the energy before and after the collision.
As we saw in Newton’s laws, momentum and impulse, linear momentum is always conserved, and as we saw in Conservation of energy, energy is always conserved. This means that for elastic collisions we can work out unknown masses and speeds using
You may need to consider energy types other than kinetic, for example potential and work done.
These sorts of calculations are used a lot at university level, and you may need to solve more complicated equations than at A level, but the theory remains the same.
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