Unit 4 - Waves PreTest

Name (First and Last)

Period

• 2
• 3
• 4
• 5
• 6

1. A rug sits in a sunny place on the floor for a long time. Kiara thinks that light from the sun can cause the rug’s color to fade over time. Can light from the sun cause the rug’s color to fade?

• A. No. Light is not a physical thing, so it cannot change physical things like rugs.
• B. No. Light can only change things by warming them up, so it cannot cause the rug’s color to fade.
• C. Yes. The rug can absorb energy from the light, causing the rug’s color to fade.
• D. Yes. Light from the sun can pull energy out of the rug, causing the rug's color to fade.

2. Roberto uses some glue to fix a broken plate. He puts the glue under a desk lamp but the glue doesn’t dry. Then he puts the glue out in the sun and it dries. Why does light from the sun dry the glue when light from the desk lamp does not?

• A. Because the glue can absorb energy from the light from the sun, but not from the light from the lamp.
• B. Because light from the sun pulls energy out of the glue and light from the desk lamp does not.
• C. Because the sun gives off a type of light that carries energy, and light from the desk lamp does not.
• D. Because light from the sun carries heat molecules, and light from the desk lamp does not.

3. Your friends say that they saw a special nail polish that changes color when it is out in the sun. Can light from the sun cause the nail polish to change color?

• A. No. Light is not a physical thing, so it cannot change physical things like nail polish.
• B. Yes. Light from the sun can pull energy out of the nail polish, causing it to change color.
• C. Yes. The nail polish can absorb energy from the light, causing it to change color.
• D. No. Light can only change things by warming them up, so it cannot cause the nail polish to change color.

4. Paintings in museums have to be kept away from ultraviolet light. Ultraviolet light will cause the paint to fade, but the overhead lamps in a museum won’t cause the paint to fade. Why does the ultraviolet light cause the paint to fade when light from the overhead lamps does not?

• A. Because ultraviolet light pulls energy out of the paint, and light from the overhead lamps does not.
• B. Because ultraviolet light carries energy, and light from the overhead lamps does not.
• C. Because the paint can absorb energy from ultraviolet light but not from the light from the overhead lamps.
• D. Because ultraviolet light carries heat molecules, and light from the overhead lamps does not.

5. Priyanka has some red marbles. She notices that sometimes the marbles get warm after being exposed to light. She wonders what type of light can cause the marbles to get warm. The table below shows what happens when different types of light hit the marbles.

• A. The X-ray light can cause the marbles to get warm.
• B. The infrared light can cause the marbles to get warm.
• C. The red light can cause the marbles to get warm.
• D. Any of these types of light can cause the marbles to get warm, because all light carries energy that can cause materials to change.

6. What does the letter D indicate in the following diagram?

• A. The wavelength of the wave
• B. The peak of the wave
• C. The amplitude of the wave
• D. The wave's trough

7. What is the letter A indicating in the following diagram?

• A. The wave's wavelength.
• B. The peak of the wave.
• C. The amplitude of the wave.
• D. The wave's trough.

8. What is the difference between digital and analog signals?

• A. DIGITAL signals are continuous and can be any value; and ANALOG signals are not continuous and jumps between distinct values.
• B. ANALOG signals are continuous and can be any value; and DIGITAL signals are not continuous and jumps between distinct values.