Conservation of Momentum!

In Thursday's class we learnt about the laws of conservation of momentum. We learnt that initial momentum is equal to final momentum. An isolated system is one where no external net force acts on the system. There are four types of explosions and collisions.

1. Explosion from rest: M1V1 = -M2V2
2. Explosion from motion: (M1+M2)Vi = M1Vf1+M2Vf2
3. Elastic Collision: M1V1i+M2V2i = M1V1f+M2V2f
4. Inelastic Collision: M1V1i+M2V2i = (M1+M2)Vf

Example: A 0.205 kg hockey puck moving at 51 m/s is caught by a 80.0 kg goalie at rest. With what speed does the goalie slide on the ice?

M1V1i+M2V2i = (M1+M2)Vf
Vf = M1V1i / M1+M2
Vf = (0.205kg)(51m/s) / (80.0kg+0.205kg)
Vf = 0.13m/s



Next up is Susanne