Dynamics of Multiple Particles

So far we have considered only the dynamics of a single particle subject to an externally imposed potential energy. The particle has no way of influencing this external agent. In the real world particles interact with each other. In this chapter we learn how this happens.

We first rewrite Newton's second law in terms of momentum. This is useful in the subsequent consideration of Newton's third law, which leads to the principle of the conservation of momentum. Collisions between particles and the behavior of rockets and conveyor belts are then studied as applications of the conservation laws to more than one particle.