Question

A small pickup truck that has a camper shell slowly coasts toward a red light with negligible friction. Two dogs in the back of the truck are moving and making various inelastic collisions with each other and the walls. What is the effect of the dogs on the motion of the center of mass of the system (truck plus entire load)? What is their effect on the motion of the truck?

a) Dogs have no effect on center of mass; truck slows down.
b) Dogs affect center of mass; truck slows down.
c) Dogs affect center of mass; truck maintains constant speed.
d) Dogs have no effect on center of mass; truck maintains constant speed.

Answer 1

The dogs in the truck affect the center of mass of the system while causing the truck to slow down.

Step-by-step explanation:

The dogs in the back of the truck affect the motion of the center of mass of the system (truck plus entire load). When the dogs collide with each other and the walls in an inelastic collision, they cause the center of mass of the system to shift. This is because an inelastic collision causes objects to stick together and redistribute their masses, thereby affecting the position of the center of mass.

The dogs also affect the motion of the truck. In an inelastic collision, some of the dogs' momentum is transferred to the truck, causing the truck to slow down. Therefore, the correct answer is option a) Dogs have no effect on center of mass; truck slows down. The center of mass is affected by the dogs, while the truck itself slows down due to the transfer of momentum.