89 terms

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

1. The law of reflection says that
a. the angle of reflection from a mirror equals the angle of
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.
2. When a virtual image is created in a plane mirror
a. the image is upright.
b. the image is located behind the mirror.
c. reflected rays diverge.
d. all of the above
e. none of the above
3. The reason we can read print from any direction is that
a. the white part of a page reflects light in all directions.
b. letters emit black light in all directions.
c. letters absorb black light from all directions.
d. all of the above
e. none of the above
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
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
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.
7. Refraction is caused by
a. different wave speeds.
b. more than one reflection.
c. displaced images.
d. bending.
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
9. You can hear noises a long distance away over water at night
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.
10. The average speed of light is greatest in
a. orange glass.
b. blue glass.
c. red glass.
d. green glass.
e. It is the same in all of the above.
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.
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
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
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.
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.
16. The effect that we call a mirage has most to do with
a. reflection.
b. refraction.
c. diffraction.
d. interference.
e. scattering.
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.
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
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.
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.
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
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.
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.
24. In a double rainbow, the outermost color in the outermost bow is
a. blue.
b. green.
c. red.
d. any of these at different times
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
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.
27. Ninety percent of light incident on a certain piece of glass passes
through it. How much light passes through two pieces of this
a. 81%
b. 85%
c. 89%
d. 90%
e. 80%
28. A converging lens
a. converges parallel rays of light.
b. refracts parallel rays of light.
c. is thicker in the center than at the edges.
d. bends parallel rays of light so they cross at a single point.
e. all of the above
29. An image of a distant object formed by a single converging lens
a. is upside down.
b. can be focused on a screen.
c. is real.
d. can be projected on a wall.
e. all of the above
30. An image formed by a single diverging lens
a. is upside down.
b. can be projected on a wall.
c. is virtual.
d. is larger than the object.
e. all of the above
31. A magnifying glass is a
a. diverging lens.
b. combination of diverging and converging lenses.
c. converging lens.
32. In drawing a ray diagram, rays can be drawn
a. from the tip of the object arrow.
b. through the focal point in front of the lens.
c. parallel to the principal axis of the lens.
d. through the center of the lens.
e. all of the above
33. If an object is located between the focal point and a converging
lens, the image will be
a. larger than the object.
b. real.
c. upside down.
d. all of the above
e. none of the above
34. If an object is located inside the focal length of a diverging lens,
then compared to the object, the image will be
a. smaller.
b. larger.
c. the same size.
35. If an object is located inside the focal length of a converging lens,
the image will be
a. right-side up.
b. upside down.
36. Suppose you hold a converging lens in front of a window. An
image of some distant hills can be focused on your hand, behind
the lens. The focal point of this lens is located
a. approximately at your hand.
b. behind your hand.
c. in front of your hand.
37. Which instrument is a human eye most similar to?
a. telescope
b. microscope
c. slide projector
d. camera
38. A simple astronomical telescope consists of
a. condenser lenses, prisms, and a projection lens.
b. a pair of converging lenses.
c. several sets of lenses that focus an image on the eye.
d. a single lens that focuses an image on a piece of film.
e. none of the above
39. The objective lens in a compound microscope forms a
a. real image.
b. virtual image.
40. The eyepiece of a compound microscope forms a
a. virtual image.
b. real image.
41. When slides are put upside down into a projector, the images are
a. upside down.
b. right-side up.
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.
43. The image your eye receives is
a. upside down.
b. right-side up.
44. If a person's eyes cannot form sharp images at any distance, the
a. has astigmatism.
b. is nearsighted.
c. is farsighted.
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.
46. The eyes of nearsighted people focus light
a. behind the retina.
b. in front of the retina.
c. at the retina.
47. Farsighted people need to wear glasses that contain
a. neither converging nor diverging lenses.
b. diverging lenses.
c. converging lenses.
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
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
50. A magnifying glass under water will magnify
a. less.
b. the same.
c. more.
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.
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.
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
d. light waves bend slightly when passing through an opening.
e. all points on a wave front are connected.
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.
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.
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.
57. Diffraction occurs for
a. radio waves.
b. X-rays.
c. light.
d. electron beams.
e. all of the above.
58. FM radio waves are not received as well as AM radio waves are in
mountain canyons because
a. they have a higher wavelength.
b. they have a shorter wavelength.
c. they do not have a high enough amplitude.
d. they do not refract as well.
59. An interference pattern is produced when
a. two or more light waves meet.
b. the crests of two waves meet.
c. the troughs of two waves meet.
d. light passes through two narrow slits.
e. all of the above
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.
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
62. Waves diffract the most when their wavelengths are
a. long.
b. short.
c. neither of the above.
63. Constructive interference occurs when
a. the crest of one wave meets the trough of another wave.
b. two waves of the same color overlap.
c. the crests of two waves overlap.
d. all of the above
e. none of the above
64. Destructive interference occurs when
a. the crests of two waves overlap.
b. two waves of the same color overlap.
c. the crest of one wave meets the trough of another wave.
d. all of the above
e. none of the above
65. When monochromatic light shines through two closely spaced
narrow slits and onto a screen some distance away, the pattern on
the screen has
a. no light in it.
b. two large bright spots.
c. alternating dark and light bands.
d. one large bright spot.
e. none of the above
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
67. If you shine monochromatic light onto two plates of glass, one
atop the other, you will see light and dark fringes. The reason for
this is that light
a. refracted from one plate interferes with light refracted from the
other plate.
b. is diffracted as it passes through the glass.
c. reflected from one plate interferes with light reflected from the
other plate.
d. is partially blocked by tiny threads of metal in the glass.
e. is scattered by ridges and valleys in the glass.
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.
69. A thin film appears blue when illuminated with white light. The
color being canceled by destructive interference is
a. green.
b. red.
c. blue.
d. white.
e. none of the above
70. Coherent light is many different rays of light all having the same
a. frequency.
b. wavelength.
c. phase.
d. direction.
e. all of the above
71. A hologram is most similar to a
a. diffraction grating.
b. prism.
c. 3-D photograph.
d. compound lens.
72. Holograms exist because of
a. diffraction.
b. interference.
c. both A and B
d. none of the above
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.
74. Interference can be shown by using
a. water waves.
b. light waves.
c. sound waves.
d. all of the above
e. none of the above
75. Monochromatic light refers to light that is
a. red.
b. white.
c. one color.
d. a chrome color.
e. all of the above
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°
77. What is the critical angle for light in glass that is meeting an air
a. 42°
b. 48°
c. 50°
d. 90°
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
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.
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°
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.
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.
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
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.
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.
88. Where in the sky would you expect to see a rainbow in the
a. northern sky
b. southern sky
c. eastern sky
d. western sky
89. A beam of light crosses a boundary between two different media.
Refraction can occur if
a. the angle of incidence is O Degrees
b. all of the light is refracted
c. the media have different indices of refraction
d. there is no change in the speed of the wave
90. In which substance does light travel the slowest?
a. crown glass
b. water
c. air
d. diamond
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