Question

In trial 1 of an experiment, a guinea pig slides with speed v0 on a frictionless, horizontal air hockey table and collides elastically with a hamburger that was initially at rest. In trial 2, the setup is identical except that the guinea pig grabs onto the hamburger and rides it.How does the speed of the guinea pig-hamburger system’s center of mass change, if at all, during the collision in each trial?Trial 1Trial 2Does not changeDoes not changeTrial 1Trial 2DecreasesDecreasesTrial 1Trial 2Does not changeDecreasesTrial 1Trial 2DecreasesDoes not change

Answer 1

Trial 1: the speed does not change

Trial 2: the speed decreases.

Step-by-step explanation

We want to determine what happens to the speed of the system's change of mass in both trials.

Trial 1 represents an elastic collision. In an elastic collision, both kinetic energy and momentum are conserved. This implies that there is no net loss in kinetic energy of the system's center of mass. Since there is no loss in kinetic energy, the speed of the system remains the same.

Trial 2 represents an inelastic collision. In an inelastic collision, the momentum of the system is conserved but the kinetic energy is not. There is a net loss in kinetic energy in this type of collision. Since there is a loss in kinetic energy, it implies that the speed of the system decreases.

Therefore, for Trial 1, the speed does not change but for Trial 2, the speed decreases..