Deck 7: Optics and Wave Effects

Question 1

The bending of waves around corners is called

A) reflection.
B) refraction.
C) diffraction.
D) interference.

Answer 1

C

Question 2

A flashlight beam is seen because of

A) specular reflection.
B) diffuse reflection.
C) dispersion.
D) refraction.

Answer 2

B

Question 3

The speed of light in a particular transparent medium is 2/8 the speed of light in a vacuum. What is the index of refraction of the material?

A) 1.3
B) 0.75
C) 4
D) 0.25

Answer 3

C

Question 4

A light wave traveling in air strikes a plane mirror surface at an angle of 30° relative to the normal. The wave is reflected at an angle of

A) 30° relative to the surface.
B) 30° relative to the normal.
C) 60° relative to the normal.
D) none of these.

Question 5

A rainbow results from

A) both reflection and refraction.
B) refraction only.
C) neither reflection nor refraction.
D) reflection only.

Question 6

A particular material has an index of refraction of 2.75. What percent of the speed of light in vacuum is the speed of light in the material?

A) 36%
B) 10%
C) 8%
D) 89%

Question 7

When the Sun is on the horizon, it is actually lower than it appears because of

A) refraction.
B) dispersion.
C) scattering.
D) reflection.

Question 8

The angle of incidence of a light wave is

A) different depending on whether there is diffuse or specular reflection.
B) measured from a normal to the surface.
C) equal to the angle of refraction.
D) measured relative to the surface of the material.

Question 9

The index of refraction of transparent materials is

A) equal to 1.
B) greater than 1.
C) less than 1.
D) any of these.

Question 10

The bending of light because of a speed change as it moves from one medium to another is called

A) diffraction.
B) refraction.
C) reflection.
D) the Doppler effect.

Question 11

A reflected ray of light leaves a plane mirror's surface at an angle of 60° relative to the normal. The angle of incidence was

A) 60° relative to the surface.
B) 60° relative to the normal.
C) 90° from the surface.
D) none of these.

Question 12

A reflected ray of light leaves a plane mirror's surface at an angle of 30° relative to the normal. The angle of incidence was

A) 30° relative to the surface.
B) 60° relative to the normal.
C) 90° from the surface.
D) none of these.

Question 13

Which of the following statements is true of the angles of incidence and reflection?

A) They are not related
B) They can never be equal
C) They are always equal
D) They add to 90°.

Question 14

The speed of light in a material is 1.74 × 10⁸ m/s. What is the index of refraction of this material?

A) 1.72
B) 0.58
C) 1.74
D) 0.218

Question 15

A ray of light in water strikes an air-water interface at an angle of incidence greater than the critical angle. The ray

A) emerges but is bent away from the normal.
B) travels along the interface.
C) emerges but is bent toward the normal.
D) is totally reflected into the water.

Question 16

The ratio of the speed of light in a vacuum to the speed of light in a medium is known as the index of

A) reflection.
B) refraction.
C) diffraction.
D) none of these.

Question 17

A pencil partially submerged in a glass of water appears broken or offset because of

A) polarization.
B) diffraction.
C) interference.
D) refraction.

Question 18

The law of reflection applies to

A) specular reflection.
B) diffuse reflection.
C) irregular reflection.
D) all of these.

Question 19

The law of reflection

A) applies only to plane mirrors.
B) is limited to regular reflection.
C) must be modified for diffuse reflection.
D) applies to all reflecting surfaces.

Question 20

The angles of incidence and reflection

A) are not related.
B) can never be equal.
C) are measured from a normal to the reflecting surface.
D) add to 90°.

Question 21

The change in the direction of a wave resulting from its encountering a small slit is known as

A) interference.
B) diffraction.
C) reflection.
D) polarization.

Question 22

An example of a diverging spherical mirror is

A) a bathroom mirror.
B) a round Christmas tree ornament.
C) a flashlight reflector.
D) none of these.

Question 23

Light for which the electric field vector is restricted to one plane is said to be

A) linearly polarized.
B) linearly refracted.
C) linearly reflected.
D) unpolarized.

Question 24

All real images

A) cannot be focused on a screen.
B) are erect.
C) can be focused on a screen.
D) are inverted.

Question 25

An object is placed 10 cm to the left of a converging spherical lens. The lens has a focal length of f = 5 cm. Where is the image formed?

A) 3.3 cm to the left of the lens
B) 3.3 cm to the right of the lens
C) 10 cm to the left of the lens
D) 10 cm to the right of the lens

Question 26

The bending of light rays around corners is called

A) reflection.
B) refraction.
C) interference.
D) diffraction.

Question 27

When light enters a denser medium and is refracted,

A) the wavelength is unchanged.
B) the wave speed increases.
C) the frequency is unchanged.
D) the wavelength increases.

Question 28

An object is placed 5 cm to the left of a converging spherical lens. The lens has a focal length of f = 15 cm. Where is the image formed and what kind of image is formed?

A) 7.5 cm to the right of the lens, Real
B) 7.5 cm to the left of the lens, Virtual
C) 7.5 cm to the right of the lens, Virtual
D) 7.5 cm to the left of the lens, Real

Question 29

A liquid crystal display (LCD) using a "twisting" effect in the display involves

A) polarization.
B) interference.
C) refraction.
D) diffraction.

Question 30

Polarization involves

A) the orientation of field vectors.
B) only longitudinal waves.
C) diffraction.
D) interference.

Question 31

The trapping of light in "light pipes," or fiber optics, is due to

A) total internal reflection.
B) refraction.
C) absorption of the outside light.
D) diffraction.

Question 32

An example of a converging spherical mirror is a

A) flashlight reflector.
B) bathroom mirror.
C) spherical truck mirror.
D) hubcap.

Question 33

If a ray of light passes from air into glass, the angle of incidence will be

A) less than the angle of refraction.
B) sometimes greater and sometimes less than the angle of refraction.
C) greater than the angle of refraction.
D) equal to the angle of refraction.

Question 34

A concave mirror will produce

A) only inverted images.
B) real or virtual images.
C) only virtual images.
D) only real images.

Question 35

If a ray of light passes from air into glass, the light will

A) travel along the normal.
B) bend toward the normal.
C) bend away from the normal.
D) continue traveling in the same direction.

Question 36

An object is placed 5 cm to the left of a converging spherical lens. The lens has a focal length of f = 10 cm. What kind of image is formed and what is its orientation?

A) Real/Upright
B) Virtual/Upright
C) Virtual/Inverted
D) Real/Inverted

Question 37

The separation of white light into its component colors is called

A) polarization.
B) diffraction.
C) dispersion.
D) refraction.

Question 38

Dispersion occurs in a medium because

A) the index of refraction depends on wave amplitude.
B) of regular reflection.
C) of diffuse reflection.
D) the index of refraction depends on the wavelength.

Question 39

An object is placed at the center of curvature of a concave mirror. The image is

A) inverted, real, and the same size as the object.
B) virtual and the same size as the object.
C) virtual and smaller than the object.
D) virtual and enlarged.
E) erect, real, and the same size as the object.

Question 40

The observation of a "wet spot" on a hot highway in the summer is caused by

A) dispersion.
B) diffraction.
C) refraction.
D) reflection.

Question 41

The image of a real object formed by a single converging lens cannot be

A) real, inverted, and enlarged.
B) real, inverted, and the same size as the object.
C) virtual, upright, and enlarged.
D) real, inverted, and reduced.
E) virtual, upright, and reduced.

Question 42

A lens that is thicker at the edge than at the center is

A) a diverging lens only.
B) a convex lens only.
C) a converging lens only.
D) both a convex lens and a converging lens.

Question 43

A visual defect wherein a person can see nearby objects clearly but not distant objects is called

A) dispersion.
B) destructive interference.
C) farsightedness.
D) nearsightedness.

Question 44

For normal vision, an object can be seen clearly when it is beyond the

A) far point.
B) nearsighted point.
C) farsighted point.
D) near point.

Question 45

A diverging lens produces an image of a real object. This image is

A) reduced, upright, and virtual.
B) enlarged, inverted, and real.
C) reduced, inverted, and virtual.
D) enlarged, upright, and real.
E) enlarged, upright, and virtual.

Question 46

A change in the direction of a wave resulting from its meeting an opaque material is called ______________.

Question 47

The image of an object at the focal point of a concave spherical mirror

A) looks the same as the object.
B) is said to be formed at infinity.
C) is real.
D) is reduced.

Question 48

A visual defect wherein a person can see distant objects clearly but not nearby objects is called

A) dispersion.
B) destructive interference.
C) farsightedness.
D) nearsightedness.

Question 49

For total internal reflection, light is ______________ and none is ______________.

A) refracted; reflected
B) refracted; transmitted
C) reflected; transmitted
D) transmitted; reflected

Question 50

Images of objects are formed by lenses because of

A) refraction.
B) diffraction.
C) internal reflection.
D) all of these.

Question 51

A lens that is thicker at the center than at the edge is

A) a diverging lens only.
B) a convex lens only.
C) a converging lens only.
D) both a convex lens and a converging lens.

Question 52

A(n) ______________ image is defined as one that cannot be brought to a focus on a screen.

A) virtual
B) real
C) upright
D) inverted

Question 53

The image of a convex mirror is always

A) virtual, inverted, and larger.
B) virtual, upright, and smaller.
C) real, upright, and smaller.
D) real, inverted, and larger.

Question 54

Reflection from smooth surfaces is called ______________ reflection.

Question 55

Optics is divided into ray optics and ______________ optics.

Question 56

A(n) ______________ image is defined as one that can be brought to a focus on a screen.

A) virtual
B) real
C) upright
D) inverted

Question 57

For total internal reflection, light is ______________ and none is ______________.

A) reflected, refracted
B) refracted; transmitted
C) transmitted, refracted
D) transmitted; reflected

Question 58

The photoreceptors responsible for "twilight" vision are called

A) rods.
B) cylinders.
C) cones.
D) cans.

Question 59

The photoreceptors responsible for color vision are called

A) rods.
B) cylinders.
C) cones.
D) cans.

Question 60

The image formed by a diverging spherical lens is always

A) upright.
B) reduced.
C) virtual.
D) all of these.

Question 61

When light enters a denser medium, the speed of the light ______________.

Question 62

Complete destructive interference occurs for two waves of the same amplitude and frequency when the waves are ______________ degrees out of phase.

Question 63

A diamond is said to have "fire" because of ______________.

Question 64

FM radio reception may be blocked by buildings because the wavelengths are too short to be ______________ around buildings.

Question 65

Reflection from rough surfaces is called ______________ reflection.

Question 66

Polarizing sunglasses have the transmission axis oriented ______________.

Question 67

According to the law of reflection, the angle of reflection is equal to ______________.

Question 68

When light strikes a transparent medium, some light is reflected and some is ______________.

Question 69

If we restrict the vibrations of the electric field vector of a wave to one direction, the wave is said to be linearly ______________.

Question 70

Total internal reflection occurs when the angle of incidence of the light is greater than the ______________ angle.

Question 71

Light traveling from a more dense to a less dense medium is refracted ______________ the normal.

Question 72

A change in the direction of a wave as a result of its encountering a sharp edge or a slit is called ______________.

Question 73

For total internal reflection, light is reflected and none is ______________.

Question 74

When a wave is ______________, the angle of reflection equals the angle of incidence.

Question 75

The change in wave motion produced by phase and amplitude relations of two or more waves is called a(n) ______________ effect.

Question 76

Liquid crystal displays (LCDs) make use of the wave phenomenon called ______________.

Question 77

A change in the direction of a wave because of a change in the velocity of the wave is called ______________.

Question 78

A(n) ______________ consists of many narrow parallel slits very close together.

Question 79

The preferential orientation of the EM field vectors of light is called ______________.

Question 80

______________ waves cannot be polarized.