3. Physics Practice Questions- Reflection/Refraction/Diffraction & Lenses Easy

44. If a person's eyes cannot form sharp images at any distance, the person a. has astigmatism. b. is nearsighted. c. is farsighted.

A ( has astigmatism.)

26. When seen from an airplane, a rainbow sometimes forms a complete circle. When this happens, the plane's shadow is a. in the center of the rainbow. b. totally outside the rainbow. c. in the upper part of the rainbow. d. Nowhere. There is no shadow. e. in the lower part of the rainbow.

A ( in the center of the rainbow.)

68. When gasoline drips on a wet street, you can see a beautiful spectrum of colors. This phenomenon is called a. iridescence. b. refraction. c. diffraction. d. construction. e. incoherence.

A ( iridescence.)

91. The speed of light in glycerol is approximately a. 2.0 x 10**8 m/s b. 1.0 x 10**7 m/s c. 4.4 x 10**8 m/s d. 3.0 x 10**8 m

A (2.0 x 10**8 m/s)

77. What is the critical angle for light in glass that is meeting an air surface? a. 42° b. 48° c. 50° d. 90°

A (42°)

27. Ninety percent of light incident on a certain piece of glass passes through it. How much light passes through two pieces of this glass? a. 81% b. 85% c. 89% d. 90% e. 80%

A (81%)

15. A beam of light emerges from water into air at an angle. The beam is bent a. away from the normal. b. not at all. c. 48 degrees upward. d. 96 degrees upward. e. towards the normal.

A (away from the normal.)

85. Assume that the following colors of light pass through a prism. Which color ray is bent the most? a. red b. blue c. green d. yellow

B (blue)

46. The eyes of nearsighted people focus light a. behind the retina. b. in front of the retina. c. at the retina.

B (in front of the retina.)

What color of light slows down the most in glass

blue

45. Sometimes after light passes through a lens, there are tiny bands of color around the edge of the image. This is due to a. chromatic aberration. b. objective aberration. c. astigmatism. d. prismatic aberration. e. spherical aberration.

A (chromatic aberration.)

81. You are standing at the edge of a swimming pool filled with water looking at a logo painted on the bottom. The logo appears to be a. closer to you than it actually is. b. further from you than it actually is. c. the same distance away as it actually is.

A (closer to you than it actually is.)

11. A penny lies in the bottom of a tea cup filled with water. As you look down on the penny, compared to its actual depth, it looks a. closer. b. farther away. c. at the same depth.

A (closer.)

7. Refraction is caused by a. different wave speeds. b. more than one reflection. c. displaced images. d. bending.

A (different wave speeds.)

71. A hologram is most similar to a a. diffraction grating. b. prism. c. 3-D photograph. d. compound lens.

A (diffraction grating)

19. The shortest plane mirror in which you can see your entire image a. is half your height. b. is twice your height. c. is equal to your height. d. cannot be determined. e. depends on how far the mirror is from you.

A (is half your height.)

50. A magnifying glass under water will magnify a. less. b. the same. c. more.

A (less.)

66. A diffraction grating consists of a. many closely spaced parallel slits. b. a criss-cross of narrow slits. c. two closely spaced parallel slits. d. a single narrow slit. e. none of the above

A (many closely spaced parallel slits)

49. Chromatic aberration occurs because different colored light rays a. refract at different angles when passing through a lens. b. pass through different part of a lens. c. focus at different places after reflection from a mirror. d. none of the above

A (refract at different angles when passing through a lens.)

1. The law of reflection says that a. the angle of reflection from a mirror equals the angle of incidence. b. waves incident on a mirror are partially reflected. c. all waves incident on a mirror are reflected. d. the angle a ray is reflected from a mirror is random.

A (the angle of reflection from a mirror equals the angle of incidence.)

17. Different colors of light travel at different speeds in a transparent medium. In a vacuum, different colors of light travel at a. the same speed. b. different speeds.

A (the same speed.)

43. The image your eye receives is a. upside down. b. right-side up.

A (upside down.)

8. Refraction occurs a. when a wave changes speed. b. only at a wave front. c. at any unpredictable time. d. only with light waves. e. all of the above

A (when a wave changes speed.)

14. The critical angle for a light from the bottom of a swimming pool shining upward toward the pool's surface is the angle a. where light is refracted so it just skims the pool surface. b. 43 degrees. c. at which all light is refracted out of the pool. d. 42 degrees. e. at which some light is reflected from the surface.

A (where light is refracted so it just skims the pool surface.)

53. Huygens' principle says that a. when light passes through two narrow slits, it produces an interference pattern. b. each point on a wave front acts as a new source of wavelets. c. when the crests of waves overlap, their individual effects add together. d. light waves bend slightly when passing through an opening. e. all points on a wave front are connected.

B ( each point on a wave front acts as a new source of wavelets.)

76. According to the figure, at what angle is light refracted if it strikes the surface of water at an angle of 30°? a. 20° b. 23° c. 42° d. 48°

B (23°)

23. In a curved optical fiber, light a. gains energy in each internal reflection. b. internally reflects in a succession of straight-line paths. c. bends and follows the curve of the fiber. d. scatters in random directions from the fiber's inner surface.

B (internally reflects in a succession of straight-line paths.)

4. An echo occurs when sound a. is transmitted through a surface. b. is reflected from a distant surface. c. changes speed when it strikes a distant surface. d. all of the above e. none of the above

B (is reflected from a distant surface.)

5. Diffuse reflection occurs when the size of surface irregularities is a. larger than 1 m in diameter. b. large compared to the wavelength of the light used. c. small compared to the wavelength of the light used. d. larger than 1 cm in diameter. e. none of the above

B (large compared to the wavelength of the light used.)

82. The critical angle for total internal reflection at an air-water interface is approximately 48°. In which of the following situations will total internal reflection occur? a. light incident in water at 40° b. light incident in water at 55° c. light incident in air at 40° d. light incident in air at 55°

B (light incident in water at 55°)

73. Magnification can be accomplished with a hologram if it is viewed with light that has a a. shorter wavelength than the original light. b. longer wavelength than the original light. c. neither of the above.

B (longer wavelength than the original light.)

87. Rainbows are due to a. reflection from the surface of raindrops. b. refraction and reflection by raindrops. c. refraction through raindrops. d. refraction and reflection by ice crystals.

B (refraction and reflection by raindrops.)

16. The effect that we call a mirage has most to do with a. reflection. b. refraction. c. diffraction. d. interference. e. scattering.

B (refraction.)

54. As you get farther and farther from a point source of waves, the wave fronts appear a. the same as when they were first created. b. straighter. c. rounder.

B (straighter.)

6. It is difficult to see the roadway from a car on a rainy night because the road surface a. is obscured by the rain itself. b. that is normally a diffuse reflector when dry becomes a mirror surface when wet. c. absorbs the light more when wet. d. scatters light in all directions.

B (that is normally a diffuse reflector when dry becomes a mirror)

55. When plane waves pass through an opening, the wave fronts will not change much if the opening is a. the same size as the wavelength. b. wide compared to the wavelength. c. narrow compared to the wavelength.

B (wide compared to the wavelength.)

72. Holograms exist because of a. diffraction. b. interference. c. both A and B d. none of the above

C ( both A and B)

83. The telephone companies are proposing using "light pipes" to carry telephone signals between various locations. The light is contained inside these pipes a. because they are coated with silver. b. as long as they are straight. c. by total internal reflection if the curves are not too sharp. d. because laser light does not travel well through air.

C (by total internal reflection if the curves are not too sharp.)

86. The dispersion of light when it passes through a prism shows that a. the prism contains many narrow, equally spaced slits. b. all colors in the light are treated the same. c. different colors have different indices of refraction. d. the speed of light in a vacuum is a constant.

C (different colors have different indices of refraction.)

56. When a wave passes through an opening, some of the wave is bent. This phenomenon is called a. polarization. b. reflection. c. diffraction. d. refraction. e. interference.

C (diffraction.)

84. If you were going to send a beam of light to the moon when it is just above the horizon, you would aim a. high b. low c. directly at the moon.

C (directly at the moon.)

22. Stars twinkle when seen from Earth at night. When seen from the moon, stars a. twinkle less. b. twinkle more. c. don't twinkle.

C (don't twinkle.)

88. Where in the sky would you expect to see a rainbow in the evening? a. northern sky b. southern sky c. eastern sky d. western sky

C (eastern sky)

51. The wavy bright and dark lines at the bottom of a swimming pool are the result of the water surface behaving like moving a. prisms. b. resonators. c. lenses. d. light absorbers.

C (lenses.)

20. When you look at yourself in a pocket mirror and then hold the mirror farther away, you see a. less of yourself. b. more of yourself. c. the same amount of yourself.

C (the same amount of yourself.)

25. A secondary rainbow is dimmer than a primary rainbow because a. only large drops produce secondary rainbows. b. sunlight reaching it is less intense. c. there is an extra reflection inside the water drops. d. it is a reflection of the primary rainbow. e. none of the above

C (there is an extra reflection inside the water drops.)

18. If you walk towards a mirror at a certain speed, your relative speed with respect to your image is a. the same as your actual speed. b. half your actual speed. c. twice your actual speed. d. none of the above

C (twice your actual speed.)

12. A mirage can occur a. when cooler air is above hotter air. b. when there's a layer of hot air close to the ground. c. on a hot day. d. all of the above e. none of the above

D (all of the above)

21. Which of the following is a consequence of the refraction of light? a. rainbows b. mirages c. internal reflection d. all of the above e. none of the above

D (all of the above)

37. Which instrument is a human eye most similar to? a. telescope b. microscope c. slide projector d. camera

D (camera)

90. In which substance does light travel the slowest? a. crown glass b. water c. air d. diamond

D (diamond)

60. Colors seen when gasoline forms a thin film on water are a demonstration of a. refraction. b. diffraction. c. dispersion. d. interference. e. polarization.

D (interference.)

78. If a ray of light strikes a pane of glass at 45° to the normal, it a. passes straight through as if the glass were not there. b. leaves the glass at a smaller angle to the normal. c. leaves the glass at a larger angle to the normal. d. leaves with the same angle to the normal, but is deflected to the side.

D (leaves with the same angle to the normal, but is deflected to the side.)

9. You can hear noises a long distance away over water at night because a. of lowered temperature. b. water conducts sound better at night. c. sound is reflected off water more efficiently at night. d. of refraction of sound in air.

D (of refraction of sound in air.)

13. When you see a "wet spot" mirage on the road in front of you, you are most likely seeing a. water. b. hot air. c. a figment of your imagination. d. sky. e. none of the above

D (sky.)

48. Spherical aberration occurs when light passes through a. the center part of a lens. b. a round lens. c. diverging lenses. d. the edges of a lens. e. none of the above

D (the edges of a lens.)

42. If light traveled at the same speed in glass as it does in air, images through a telescope would look a. larger than usual. b. smaller than usual. c. fuzzier than usual. d. the same as they would without the telescope. e. clearer than usual.

D (the same as they would without the telescope.)

52. Suppose you stand 2 m in front of a plane mirror. How far away from you is your image? a. ¼ m. b. ½ m. c. 1 m. d. 2 m. e. 4 m.

E (4 m.)

57. Diffraction occurs for a. radio waves. b. X-rays. c. light. d. electron beams. e. all of the above.

E (all of the above.)

61. Iridescent colors seen in the pearly luster of an abalone shell are due to a. refraction. b. polarization. c. dispersion. d. reflection. e. none of the above

E (none of the above)

All rays rely on light doing what and why?

bending because it slows down

why is a spectrum produced by a prism or a raindrop

different colors of light travel at different speeds, red fastest and blue the slowest

why do we use ray diagrams?

location of an image

the explanation for a filled coke bottle looking fuller than it is involves which concept?

refraction

A person standing waist deep in a swimming pool appears to have short legs because light

refracts

How does a light beam bend as it emerges from water into air?

speeds up and is bent away from the normal

When a light beam emerges from water into air, what happens to its speed?

speeds up and is bent away from the normal