Using the Collisions PhET online simulation your students will investigate elastic and inelastic collisions. To do this they will (1) apply the laws of conservation of energy and momentum to characterize the difference between elastic and inelastic collisions, (2) determine the changes in kinetic energy when energy is not conserved, (3) explain why energy is not conserved in some collisions, (4) draw before and after pictures of collisions and (5) investigate five special cases for elastic and i