Module 15

Question 1

1a. Define: electromagnetic wave

Answer 1

a transverse wave composed of an oscillating electric field and a magnetic field that oscillates perpendicular to the electric field

Question 2

1b. Define: the Law Reflection

Answer 2

the angle of reflection equals the angle of incidence

Question 3

2. Explain the wave theory of light, the particle theory of light and the quantum-mechanical theory of light.

Answer 3

The wave theory of light views light as two transverse waves, one made of an oscillation magnetic field and the other as an oscillating electric field. The particle theory of light views a ray of light as a beam of individual particles called photons. The quantum-mechanical theory says that light is bash a particle and a wave. It is made up of individual packets that behave like particles, but the packet is actually made up of a wave.

Question 4

3. Sound waves cause air to oscillate. What do light waves oscillate?

Answer 4

light waves oscillate a magnetic field and an electric field

Question 5

4. What does Einstein’s Special Theory of Relativity say about the speed of light?

Answer 5

nothing with mass can travel faster than the speed of light

Question 6

5. Light is traveling through water and suddenly breaks the surface and travels through air. Did light’s speed increase, decrease, or stay the same once it left the water?

Answer 6

the light’s speed increased once it left the water

Question 7

6. Order the following colors in terms of increasing wavelength: orange, violet, yellow, green. In other words, list the color corresponding to the smallest wavelength first, and end with the color that correspond to the longest wavelength.

Answer 7

violet, green, yellow, orange

Question 8

7. Order the colors in problem #6 (orange, yellow violet green) in terms of increasing frequency. Once again, start with the lowest frequency and end with the highest frequency.

Answer 8

orange, yellow, green, violet

Question 9

8. Do radio waves have higher or lower frequencies than visible light? What about X- rays?

Answer 9

radio waves have lower frequencies than visible light, while X- rays have higher frequencies

Question 10

9. Infrared light is given off by any object that is losing heat. The human body is almost always losing heat to the environment. Why then don’t human bodies glow at night since they are emitting light?

Answer 10

infrared light is not visible

Question 11

10. Light hits a mirror, making an angle of 15 degrees relative to a line drawn perpendicular to the mirror’s surface. What angle does the reflected light make with the same line?

Answer 11

the reflected light also makes a 15 degree angle relative to the line

Question 12

11. look in book on page 395, #11

Answer 12

yes, but look in answer key on page 38

Question 13

12. When light travels from one substance to another, what two things can happen to the direction of the light ray’s travel?

Answer 13

the light ray can be reflected or refracted

Question 14

13. In a physics experiment, a light ray is examined as it travels from air into glass. If the angle that the light ray makes with a line perpendicular to the glass surface is measured, will the refracted ray bend toward or away from that line?

Answer 14

the light will bend towards the perpendicular line

Question 15

14. When you look at objects underwater from above water, they appear to be at a different position than their actual position. Why?

Answer 15

When light travels from water to air, it bends. This causes your mind to form a false image of the object in a slightly different location.

Question 16

15. In order for you to see a rainbow, what three conditions must be met?

Answer 16

There must be water droplets suspended in the air, the sun must be shining on them from behind you, and the sun must be at a certain angle (or height in the sky).

Question 17

16. What is the difference between a converging lens and a diverging lens?

Answer 17

A converging lens causes light rays to bend so that they converge to a single point. Diverging lenses cause light rays to bend away from each other.

Question 18

17. look in book on page 396, #17

Answer 18

lens (a) is a converging lens and lens (b) is a diverging lens

Question 19

18. What is special about the way the eye focuses light as compared to the way a camera focuses light?

Answer 19

The eye focuses light by changing the shape of its lens. A camera focuses light by moving the position of the lens.

Question 20

19. Suppose the cone cells on your retina that sense red light no longer work. If you look at a white piece of paper, what color would it appear to be? If you look at a red piece of paper, what color would it appear to be?

Answer 20

the white paper would appear to be blue-green or cyan; the red paper would appear to be black

Question 21

20. A shirt is dyed so that it looks violet. What colors of light does the dye absorb?

Answer 21

thus, it absorbs red, yellow, orange, green, blue, and indigo light

Question 22

21. A cyan dye is made of a mixture of substances that absorb all light colors except blue and green. If you took a cyan piece of paper and laced it in a dark room and shined red light on it, what would you see? what would you see if you shined green light on it?

Answer 22

in red light, then, the paper would look black; in green light the paper would look green.