Physics 30 - Dec 12

Today we started looking at the law of conservation of momentum.  When no external forces are acting on a system, the system is said to be isolated.  When a system is isolated, the total momentum of the system remains constant.  This is called the law of conservation of momentum.  For our purposes, we will always assume that the system is isolated.  We looked at how this applies to explosions, or when one object becomes multiple objects.  We also looked at how this applies to collisions.  We learned about the different types of collisions.  Elastic collisions are collisions where objects collide and bounce off of each other.  In these types of collisions, momentum will be conserved.  Energy can be conserved as well if it is a perfect elastic collision.  The other type of collision is called an inelastic collision.  Momentum is conserved with these types of collisions but energy is always lost.  We didn't get a chance to work on example 21 today.  We will do that on Monday.  Reminder that on Monday we are having the radiation lab quiz.