Unit 2 Review

Which of these devices is the only one NOT designed to produce both sound and light energy?

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The picture shows an athlete hitting a ball with a tennis racquet. What is the athlete demonstrating in the picture?

• Doing work by pushing the ball and changing its motion and position

• Changing the position but not the motion of the ball

• Doing work by pulling the racquet and changing the ball’s position but not its motion

• Changing the position and motion of the ball without doing any work

Some students are feeding a crab in an aquarium. They use tongs to place the food directly in front of the crab. The students look through the side of the aquarium. They notice that the image of the tongs appears to break as the tongs enter the water. Which property of light are the students observing in this situation?

• Light can be refracted and separated into different colors as it moves from air to a different medium.

• Light is refracted as it moves from one medium to another medium.

• Light travels in a straight line and can be reflected off the surface of water.

• Light is absorbed by water and reflected off glass.

This circuit has five light-emitting diode, or LED, lights. It also has one battery and one switch. Which LEDs produce light when the switch is in the position shown?

• LEDs 1, 3, and 4 only

• LEDs 1, 2, 3, and 4

• LEDs 3 and 4 only

• LEDs 1, 3, 4, and 5

Students design an experiment to determine how much force is needed to move blocks of wood of different masses slowly across a lab table. Which procedure should students include in their design?

• Conduct five trials, using a different scale to pull each block of wood

• Conduct five trials, pulling a different side of each block each time

• Conduct five trials, using a different table for each trial

• Conduct five trials, pulling each block of wood in the same way for each trial

A student conducts an investigation by shining a flashlight toward a flat mirror. The student changes the angle of the mirror and observes the path of the reflected light. As the mirror changes direction, the light reaching the mirror can reach the ceiling because the light —

• refracts in the glass of the mirror and is spread out all over the room

• travels in straight lines and reflects from the surface of the mirror

• enters the mirror and changes direction when it is refracted by the back of the mirror

• travels through air and does not change its direction in air

A family was vacationing in the mountains in a cabin that had no electrical power. They needed boiling water in order to prepare dried soup mix. With no electrical energy available, which method would most likely provide enough thermal energy to quickly heat the water to boiling?

• Using a micorwave oven to heat water in a glass jar for 3 minutes

• Shaking the water in a closed, insulated plastic bottle for 3 minutes

• Shining a battery-powered flashlight on a metal container of water for 10 minutes

• Placing a metal pot of water over glowing charcoal in an outdoor grill for 10 minutes

The circuit above does not work. Which procedure would most likely allow the bulbs to light.

• Open the switch and then connect the two wires that are attached to the wood block.

• Switch the positions of the two wires that are connected to the battery and then open the switch

• Move the switch closer in the circuit to the batter

• Connect the two wires that are attached to the wood block

The diagram shows an electric circuit with four bells that a student plans to build. When the student connects the wires as shown, which of the bells will ring?

• Bell 1 only

• Bells 1 and 4 only

• Bells 3 and 4 only

• Bells 1, 2, 3, and 4

The toy oven shown uses a light bulb to bake small cakes. What types of energy does the toy oven use to bake the cakes?

• Electrical and thermal

• Mechanical and electrical

• Thermal and mechanical

• Light and sound