Physics Quiz

Determine if each scenario below is an example of a balanced force or an unbalanced force.

Gravity applies a force to hold down the melon (on the table). It is equal to the force that the table applies to pull down on the melon. If there were no wind, and the force of gravity was removed, the melon would —

• roll to the middle of the table.

• sink down into the table.

• roll off the table.

• float straight up.

Bobby has a toy car that is sitting at rest on the floor. He decides to play with his toy car and pushes it with 3 newtons to the right. Bobby's friend Sam also decides to play with the toy car and pushes it with 6 newtons to the left at the exact same time. Which of the following best describes the resulting motion of the toy car?

• It travels to the right at an increasing speed.

• It travels to the right at a constant speed.

• It travels to the left at an increasing speed.

• It travels to the left at a constant speed.

Charlotte rode her bike on a mountain trail. It took her 20 minutes to travel 4.5 miles on the trail. What was Charlotte's average speed in miles/minute?

Two teams are competing in a game of tug-of-war in the diagram below. Both teams are pulling with a force of 2300 newtons. What will happen if the team on the left makes an extra effort and pulls the rope with a force of 2500 newtons?

A classroom projector transforms electrical energy into — (Select 3 correct answers)

• Chemical Energy

• Electrical Energy

• Light Energy

• Thermal Energy

• Sound Energy

An object's potential energy is determined by the object's mass and its height above the ground. An object's kinetic energy is determined by the object's mass and its —

Fireworks transform chemical energy into —

• mechanical energy and sound energy.

• heat energy and light energy.

• mechanical energy and electrical energy.

• sound energy and electrical energy.

Unlike potential energy, kinetic energy cannot —

• be heard as sound waves.

• be stored in atomic bonds.

• travel in light waves.

• travel through electrons moving through a wire.

Kyle is riding his bicycle. He works very hard to reach the top of a hill and then coasts down the other side. Which statement best explains why Kyle does NOT need to work as hard when he travels downhill?

• No energy is lost as heat when Kyle rides downhill.

• Potential energy is converted to kinetic energy as he moves downhill.

• Kinetic energy is stored in the bicycle.

• There is less friction between the road and the bike as it moves downhill.