Deck 25: Wave Optics

Question 1

A fringe shift occurs for every ______ wavelength movement of the adjustable mirror in a Michelson interferometer. A fringe shift occurs when the intensity goes from bright to dark or when it goes from dark to bright.

A) half
B) eighth
C) quarter
D) whole

Answer 1

quarter

Question 2

What is the minimum thickness of a glycerin film (n = 1.47) on which light of wavelength 450 nm shines that results in constructive interference of the reflected light? Assume the film is surrounded front and back by air.

A) 150 nm
B) 76.5 nm
C) 204 nm
D) 102 nm

Answer 2

76.5 nm

Question 3

A silicon monoxide thin film (n = 1.45) of thickness 77.6 nm is applied to a camera lens made of glass (n = 1.55). This will result in a destructive interference for reflected light of what wavelength?

A) 720 nm
B) 558 nm
C) 450 nm
D) 522 nm

Answer 3

450 nm

Question 4

Two flat glass plates are in contact along one end and are separated by a sheet of paper 3.0 *10 ^{- 6} m thick at the other end. The top plate is illuminated by a monochromatic light source of wavelength 490 nm. How many dark parallel bands will be evident across the top plate? (1 nm = 10 ^{- 9} m) Note that a dark band occurs where the plates contact.

A) 13
B) 7
C) 9
D) 17

Question 5

How far, in wavelengths, does the movable mirror travel in a Michelson interferometer travel going from intensity maximum to the next intensity maximum?

A)
B)
C)
D)

Question 6

The Michelson interferometer is a device that may be used to measure:

A) magnifying power of lenses.
B) light wavelength.
C) atomic masses.
D) electron charge.

Question 7

That light can undergo interference is evidence that it:

A) has a phase of 180°.
B) has electric properties.
C) behaves like a wave.
D) is made of corpuscles.

Question 8

A beam of light of wavelength 600 nm is incident along the normal to two closely spaced parallel glass plates. For what air gap separation between the plates will the transmitted beam be of maximum intensity? (1 nm = 10 ^{- 9} m)

A) 75 nm
B) 300 nm
C) 410 nm
D) 150 nm

Question 9

The blue tint of a coated camera lens is largely caused by what effects?

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

Question 10

Two closely spaced parallel glass plates are separated by 900 nm. What wavelength light source in the visible region (390 nm to 710 nm) will experience maximum transmission through the two plates?

A) 684 nm
B) 600 nm
C) 500 nm
D) 429 nm

Question 11

What wavelength monochromatic source in the visible region (390 to 710 nm) can be used to constructively reflect off a soap film (n = 1.46) in air if the film is 288 nm thick?

A) 561 nm
B) 480 nm
C) 587 nm
D) 467 nm

Question 12

Two beams of coherent light are shining on the same piece of white paper. With respect to the crests and troughs of such waves, darkness will occur on the paper where:

A) the crest from one wave overlaps with the crest from the other.
B) the troughs from both waves overlap.
C) the crest from one wave overlaps with the trough from the other.
D) darkness cannot occur as the two waves are coherent.

Question 13

When using 529-nm light, how far is the adjustable mirror of a Michelson interferometer moved when 600 fringe shifts are counted? A fringe shift occurs when the intensity goes from bright to dark or when it goes from dark to bright.

A) 1.58 * 10^-4 m
B) 7.94* 10^-5 m
C) 9.90 *10^-6 m
D) 3.97 * 10^-5 m

Question 14

What wavelength monochromatic source in the visible region (390 to 710 nm) can be used to constructively reflect off a soap film (n = 1.46) in air if the film is 70.0 nm thick?

A) 558 nm
B) 430 nm
C) 450 nm
D) 409 nm

Question 15

In order to produce a sustained interference pattern by light waves from multiple sources, which of the following conditions must be met?

A) Sources are monochromatic.
B) Sources are coherent.
C) Both choices a and b are valid.
D) None of these are valid.

Question 16

Waves from a radio station with a wavelength of 900 m arrive at a home receiver a distance 50 km away from the transmitter by two paths. One arrives via a direct-line path and the second by reflection from a mountain directly behind the receiver. What is the minimum distance between the mountain and receiver such that destructive interference occurs at the location of the listener? Assume no phase change on reflection.

A) 675 m
B) 900 m
C) 450 m
D) 225 m

Question 17

Light travels from inside a building to outside through a pane of glass. Which of the following is true regarding the phase change upon reflection in the case?

A) A 180^o phase change occurs at the inside surface but not at the outside surface.
B) A 180^o phase change occurs at the outside surface but not at the inside surface.
C) A 180^o phase change occurs at both the inside surface and the outside surface.
D) No phase change occurs at either the inside surface or the outside surface of the glass.

Question 18

A silicon monoxide (n = 1.45) film of 330 nm thickness is used to coat a glass camera lens (n = 1.56). What wavelength of light in the visible region (390 to 710 nm) will be most efficiently transmitted by this system? (1 nm = 10 ^{- 9} m)

A) 522 nm
B) 492 nm
C) 638 nm
D) 409 nm

Question 19

Light of wavelength 500 nm shines on a soap bubble film (n = 1.46). For what soap film thickness, other than the minimum thickness, will constructive interference occur?

A) 63 nm
B) 102 nm
C) 308 nm
D) 257 nm

Question 20

The Michelson interferometer can make precise length measurements using which of the following phenomena?

A) resolving power
B) magnification
C) force
D) interference

Question 21

A Young's double-slit experiment is performed in air and then the apparatus is submerged in water. What happens to the fringe separation, and what can be used to explain the change, if any?

A) The separation decreases because the frequency of the light decreases in the water.
B) The separation decreases because the wavelength of the light decreases in the water.
C) The separation stays the same as it is the same experiment independent of the medium.
D) The separation increases because the wavelength of the light increases in the water.

Question 22

When light passes from a material with a low index of refraction into material with a high index of refraction:

A) some light is reflected with a 180° change of phase.
B) none of the light is reflected.
C) some light is reflected without a change of phase.
D) the light that is not reflected has a 180° change of phase.

Question 23

A surface is coated with a material having index of refraction 1.50. If light in air has a wavelength of 450 nm and is normally incident on this surface, and it is found through interference effects with this light that the surface is 15 wavelengths thick, which of the following is the thickness of the surface?

A) 6.8 $\mu$ m
B) 1.5 $\mu$ m
C) 3.0 $\mu$ m
D) 4.5 $\mu$ m

Question 24

A soap bubble (n = 1.35) is floating in air. If the thickness of the bubble wall is 322 nm, which of the following wavelengths of visible light is strongly reflected?

A) 540 nm (green)
B) 620 nm (red)
C) 500 nm (blue)
D) 580 nm (yellow)

Question 25

Two flat glass plates are in contact along one end and are separated by a sheet of tissue paper at the other end. A monochromatic source of wavelength 490 nm illuminates the top plate. If 20 dark bands are counted across the top plate, what is the paper thickness? (1 nm = 10 ^{- 9} m) Note that a dark band occurs where the plates contact.

A) 2.7 *10 ^{- 6} m
B) 3.4 * 10 ^{- 6} m
C) 4.7 *10 ^{- 6} m
D) 4.9*10 ^{- 6} m

Question 26

A thin film ( ) of thickness 77.6 nm, applied to a camera lens ( ), is the minimum thickness that results in destructive interference for reflected light of wavelength 450 nm. which of the following is the next greater thickness that will also give destructive interference for this wavelength?

A) 120 nm
B) 155 nm
C) 116 nm
D) 233 nm

Question 27

A silicon monoxide (n = 1.45) film of 108 nm thickness is used to coat a glass camera lens (n = 1.56). What wavelength of light in the visible region (390 to 710 nm) will be most efficiently transmitted by this system? (1 nm = 10 ^{- 9} m)

A) 580 nm
B) 400 nm
C) 492 nm
D) 626 nm

Question 28

A possible means for making an airplane radar-invisible is to coat the plane with an antireflective polymer. If radar waves have a wavelength of 3.84 cm, and the index of refraction of the polymer is n = 1.6, how thick would the coating be if a 180° phase change occurs at both surfaces?

A) 24 mm
B) 7.5 mm
C) 32 mm
D) 6.0 mm

Question 29

A puddle of water (n = 1.33) is covered with a very thin layer of oil (n = 1.20). How thick is the oil in the region that strongly reflects light with a wavelength of 497 nm?

A) 207 nm
B) 550 nm
C) 458 nm
D) 229 nm

Question 30

Interference effects observed in the early 1800s were instrumental in supporting a concept of the existence of which property of light?

A) electromagnetic character
B) particle nature
C) wave nature
D) polarization

Question 31

Upon reflection, light undergoes no phase change:

A) if the incident medium has the lower index of refraction.
B) if the incident medium has the higher index of refraction.
C) always.
D) whenever the incident angle is less than the critical angle.

Question 32

A Young's double slit has a slit separation of 2.50 *10 ^{- 5} m on which a monochromatic light beam is directed. The resultant bright fringes on a screen 1.00 m from the double slit are separated by 2.30 *10 sup>- ² m. What is the wavelength of this beam? (1 nm = 10 ^{- 9} m)

A) 575 nm
B) 454 nm
C) 373 nm
D) 667 nm

Question 33

Two narrow slits are 0.025 mm apart. When a laser shines on them, bright fringes form on a screen that is a meter away. These fringes are 1.3 cm apart. What is the separation between the m = 2 bright fringe and the central fringe?

A) 2.6 cm
B) 5.3 cm
C) 8.6 cm
D) 6.0 cm

Question 34

Light is reflecting off a wedge-shaped thin piece of glass producing bright and dark interference fringes. If a certain location has a bright fringe, a nearby point will have a bright fringe if the thickness of the glass increases by:

A) one wavelength of the light.
B) 1/4 of a wavelength of the light.
C) 1/8 of a wavelength of the light.
D) 1/2 of a wavelength of the light.

Question 35

If a wave from one slit of a Young's double-slit set-up arrives at a point on the screen one-half wavelength behind the wave from the other slit, what is observed at that point?

A) dark fringe
B) bright fringe
C) gray fringe, neither dark nor bright
D) multi-colored fringe

Question 36

A hair is placed at one edge between two flat glass plates. When this arrangement is illuminated with yellow light of wavelength ( $\lambda$ = 600 nm), a total of 61 dark bands are counted starting at the point of contact between the plates. How thick is the hair? (1 nm = 10 ^{- 9} m) Note that a dark band occurs where the plates contact.

A) 3.6 *10 ^{- 4} m
B) 1.8 *10 ^{- 4} m
C) 1.8 *10 ^{- 5} m
D) 3.6 * 10 ^{- 5} m

Question 37

That all points on a wave front act as new sources of spherical waves is attributed to:

A) Maxwell.
B) Young.
C) Thomas.
D) Huygens.

Question 38

In a Young's double-slit experiment, both the wavelength and the slit separation are increased by 25%. What happens to the distance between two adjacent bright fringes?

A) It decreases by 50%.
B) It increases by 50%.
C) The distance increases by 25% or more.
D) The distance stays the same.

Question 39

Two thin layers of material with different indices of refraction are coated on a glass plate. The outer first material has n₁ = 1.404, the inner second material has n₂ = 1.176, and the glass has n_glass = 1.62. If light is incident from air on the first layer, what is the phase change relative to that of the first layer reflection for light that reflects from the glass?

A) 180°
B) 540°
C) 360°
D) 0°

Question 40

In a Young's double-slit experiment, what happens to the angular separation between the fringes when the wavelength is decreased at the same time that the slit separation is increased?

A) The relative sizes of the changes need to be known before a definite answer can be given.
B) It increases.
C) It decreases.
D) It stays the same.

Question 41

In the straight-ahead direction ( $\theta$ = 0°) in single-slit diffraction, which of the following is observed on the screen?

A) a maximum double in width to the adjacent maxima
B) a minimum double in width to the adjacent minima
C) a maximum equal in width to the adjacent maxima
D) a minimum equal in width to the adjacent minima

Question 42

A Young's double-slit apparatus is set up. A screen is positioned 1.16 m from the double slits, and the spacing between the two slits is 0.0500 mm. The distance between alternating bright fringes is 1.42 cm. What is the light source wavelength? (1 nm = 10 ^{- 9} m)

A) 612 nm
B) 280 nm
C) 490 nm
D) 355 nm

Question 43

Helium-neon laser light ( $\lambda$ = 632.8 nm) is sent through a single slit of width 0.41 mm. What is the width of the central maximum on a screen 1.0 m in back of the slit? (1 nm = 10 ^{- 9} m)

A) 5.3 mm
B) 4.2 mm
C) 3.1 mm
D) 2.0 mm

Question 44

In a Young's double-slit experiment, by how many wavelengths do the paths from the slits to the screen differ for the m = 3 and the m = 8 minima?

A) 10
B) 2.5
C) 5
D) Some other value than those given since this is for destructive interference.

Question 45

A Young's double-slit apparatus is set up. The source wavelength is 430 nm, and the double-slit spacing is 0.040 mm. At what distance from the double slits should the screen be placed if the spacing between alternating bright fringes is to be 2.6 cm? (1 nm = 10 ^{- 9} m)

A) 2.9 m
B) 2.4 m
C) 2.2 m
D) 1.6 m

Question 46

A single-slit diffraction pattern is produced from a light source of wavelength 580 nm. The light goes through a single slit and onto a screen 1.0 m away. The first dark fringe is 5.8 mm from the central bright fringe. What is the slit width? (1 nm = 10 ^{- 9} m)

A) 0.12 mm
B) 0.24 mm
C) 0.081 mm
D) 0.10 mm

Question 47

In a Young's double-slit experiment, how many maxima occur between the m = +3 and m = -3 maxima?

A) 6
B) 8
C) 7
D) Not given.

Question 48

A Young's double-slit apparatus is set up so that a screen is positioned 1.6 m from the double slits, and the spacing between the two slits is 0.0315 mm. What is the distance between alternating bright fringes on the screen if the light source has a wavelength of 630 nm? (1 nm = 10 ^{- 9} m)

A) 0.016 m
B) 0.047 m
C) 0.025 m
D) 0.032 m

Question 49

In a Young's experiment, the paths from the slits to a point on the screen differ in length, causing constructive interference at the point. Which of the following path differences would cause this constructive interference?

A) 5 $\lambda$ /2
B) 3 $\lambda$
C) 3 $\lambda$ /4
D) None of these choices.

Question 50

In a Young's double-slit interference apparatus, by what factor is the distance between adjacent light and dark fringes changed when the separation between slits is tripled?

A) 1/9
B) 1
C) 3
D) 1/3

Question 51

In a Young's experiment, the paths from the slits to a point on the screen differ in length, causing destructive interference at the point. Which of the following path differences would cause this destructive interference?

A) 3 $\lambda$ /2
B) 4 $\lambda$
C) 5 $\lambda$
D) None of these choices.

Question 52

After light from a source passes through two slits, a m = 1 bright spot is seen on the wall at point P. Which distance is equal to the wavelength of the light?

A) the distance between slits
B) the distance between beams as they leave the slit
C) the extra distance one beam must travel
D) the distance of point P from the central point of the interference pattern

Question 53

A light source simultaneously emits light of two wavelengths, 480 nm and 560 nm, respectively. The source is used in a double-slit interference experiment where the slit spacing is a 0.040 mm, and the distance between double slits and the screen is 1.6 m. What is the separation between the m = 3 bright fringes of the two wavelengths as they appear on the screen? (1 nm = 10 ^{- 9} m)

A) 0.96 cm
B) 0.48 cm
C) 0.64 cm
D) 0.16 cm

Question 54

A Young's double-slit apparatus is set up where a screen is positioned 0.80 m from the double slits. If the distance between alternating bright fringes is 0.83 cm, and the light source has a wavelength of 580 nm, what is the separation of the double slits? (1 nm = 10 ^{- 9} m)

A) 6.0 *10 ^{- 5} m
B) 2.8 *10 ^{- 5} m
C) 4.9 *10 ^{- 5} m
D) 5.6 *10 ^{- 5} m

Question 55

If the m = 2 fringe in Young's double-slit experiment occurs at an angle of 45.0°, what is the relationship between the wavelength $\lambda$ and the distance between slits, d?

A) d = 2.00 $\lambda$
B) d = 2.83 $\lambda$
C) d = 1.41 $\lambda$
D) d = 4.00 $\lambda$

Question 56

Laser light sent through a double slit produces an interference pattern on a screen 3.00 m from the slits. If the m = 2 maximum occurs at an angle of 10.7°, at what angle does the m = 8 maximum occur?

A) No m = 8 maximum occurs.
B) 48.0°
C) 56.3°
D) Not enough information is given.

Question 57

A Young's interference experiment is conducted with blue-green argon laser light ( $\lambda$ = 515 nm). The separation between the slits is 0.50 mm, and the interference pattern appears on a screen 4.95 m away. What is the spacing between the bright fringes? (1 nm = 10 ^{- 9} m)

A) 3.4 mm
B) 5.1 mm
C) 1.7 mm
D) 6.8 mm

Question 58

Light of wavelength 540 nm is incident on a slit of width 0.150 mm, and a diffraction pattern is produced on a screen that is 3.00 m from the slit. What is the width of the central bright fringe? (1 nm = 10 ^{- 9} m)

A) 1.44 cm
B) 0.720 cm
C) 2.16 cm
D) 1.76 cm

Question 59

Light of wavelength 610 nm is incident on a slit of width 0.20 mm, and a diffraction pattern is produced on a screen that is 2.0 m from the slit. What is the distance of the second dark fringe from the center of the central bright fringe? (1 nm = 10 ^{- 9} m)

A) 1.4 cm
B) 1.2 cm
C) 0.68 cm
D) 0.92 cm

Question 60

In a Young's double-slit interference apparatus, by what factor is the distance between adjacent light and dark fringes changed when the wavelength of the source is doubled?

A) 1/2
B) 1/4
C) 1
D) 2

Question 61

A multiple slit diffraction grating has a slit separation of 2.00 * 10 ^{- 6} m. Find the wavelength of the monochromatic light that will have its second order (m = 2) bright fringe diffracted through an angle of 43.4°. (1 nm = 10 ^{- 9} m)

A) 616 nm
B) 500 nm
C) 687 nm
D) 120 nm

Question 62

An individual's eye pupil changes from a diameter of 1.5 mm to 3.5 mm as the illumination is increased. By what factor does the minimum angle of resolution change?

A) 2.0
B) 2.3
C) 0.43
D) 0.65

Question 63

Diffraction grating #1 has twice the lines/cm that diffraction grating #2 does. When used with a certain wavelength of light, both gratings give first order (m = 1) maxima. Which of the following statements is true for the same wavelength of light.

A) Both gratings must also give second (m = 2) order maxima.
B) It is possible that neither grating gives a second order maximum.
C) Grating #1 must give a second order maximum.
D) Grating #2 must give a second order maximum.

Question 64

A wavelength of 573 nm yields a first order (m = 1) maximum at 40° with a grating. At what angle will the second order (m = 2) maximum appear for this wavelength?

A) 17.5°
B) No second order maximum exists in this case.
C) -40°
D) 80°

Question 65

A microscope has an objective lens with an aperture diameter 0.60 cm. A monochromatic light source of wavelength 580 nm is used to illuminate the object. It is determined that the minimum angle of resolution is 1.18 *10^-4 rad. If the present lens were replaced by one with an aperture of diameter 1.0 cm, what would the minimum angle of resolution now become? (1 nm = 10^-9 m)

A) 1.5 *10^-4 rad
B) 0.79 *10^-4 rad
C) 0.71 * 10^-4 rad
D) 1.8 *10^-4 rad

Question 66

If different filters are used with an astronomical telescope, which of the following would give the best resolution?

A) red
B) blue
C) green
D) All yield the same resolution.

Question 67

At what angle will the second order (m = 2) maximum occur for a wavelength of 450 nm using a diffraction grating with 10,000 lines per cm?

A) 64°
B) 27°
C) 53°
D) No second order maximum will occur in this case.

Question 68

Find the radius of a star image formed on the retina of the eye if the aperture diameter (the pupil) at night is 0.70 cm and the length of the eye is 3.0 cm. Assume the wavelength of starlight in the eye is 600 nm. (1 nm = 10 ^{- 9} m)

A) 5.2 *10^-4 m
B) 3.1 *10^-6 m
C) 2.6 *10^-6 m
D) 2.6 *10^-4 m

Question 69

In a single-slit diffraction experiment, the angular width of the central maximum is 0.16°. The width of the slit is then doubled as is the distance to the screen. What is the resulting angular width of the central maximum?

A) 0.64°
B) 0.080°
C) 0.32°
D) 0.16°

Question 70

Light with a wavelength of 450 nm shines through a lens with an aperture diameter of 0.85 cm. Use Rayleigh's criterion to determine the limiting angle of resolution. (1 nm = 10^-9 m)

A) 6.5 *10^-5 rad
B) 1.3*10^-4 rad
C) 9.2 *10^-5 rad
D) 3.0 *10^-9 rad

Question 71

A diffraction grating has 2500 lines/cm. What is the slit separation?

A) 4.0 $\mu$ m
B) 250 nm
C) 400 nm
D) 2.5 $\mu$ m

Question 72

What is the highest order (m value) maximum for wavelength 450 nm that can be obtained with a grating with 300 lines per mm?

A) 8
B) 3
C) 7
D) 4

Question 73

A laser shines 630-nm light through a grating producing a first order (m = 1) maximum at an angle of 30°. A second laser produces a first order maximum with the same grating at 20°. What is the wavelength emitted by the second laser?

A) 945 nm
B) 651 nm
C) 420 nm
D) 431 nm

Question 74

What is the highest order (the m value) of the complete visible spectrum (390 nm to 710 nm) that can be obtained with a grating having 300 lines/mm?

A) 5
B) 9
C) 8
D) 4

Question 75

A microscope has an objective lens with an aperture of diameter 0.60 cm where a monochromatic light source of wavelength 580 nm is used to illuminate the object. It is determined that the minimum angle of resolution is 1.18 *10 ^{- 4} rad. If the illuminating source were replaced by a source of wavelength 700 nm, what would the minimum angle of resolution now become? (1 nm = 10^-9 m)

A) 0.58*10^-4 rad
B) 1.4 *10^-4 rad
C) 0.85 *10^-4 rad
D) 1.2 *10^-4 rad

Question 76

In a single-slit diffraction experiment, the width of the central maximum is 6.0 mm. The width of the slit is then doubled as is the distance to the screen. What is the resulting width of the central maximum?

A) 12 mm
B) 6.0 mm
C) 24 mm
D) 3.0 mm

Question 77

At what angle will the highest order (m value) maximum appear for a wavelength 400 nm using a grating with 600 lines per mm?

A) 54°
B) 90°
C) 74°
D) 36°

Question 78

A diffraction grating with 10,000 lines/cm will exhibit the first order (m = 1) maximum for light of wavelength 264 nm at what angle? (1 nm = 10 ^{- 9} m)

A) 15.3°
B) 0.62°
C) 0.51°
D) 31°

Question 79

The 2.4-m diameter Hubble space telescope has been placed into Earth orbit by the space shuttle. Assuming a wavelength of 710 nm, what angular resolution could this telescope achieve by Rayleigh's criterion? (1 nm = 10^-9 m)

A) 5.7 *10^-6 rad
B) 7.5 *10^-6 rad
C) 3.6 *10^-7 rad
D) 2.5 *10^-7 rad

Question 80

A binary star system in the constellation Orion has an angular separation between the stars of 10^-5 radians. Assuming a wavelength of 700 nm, what is the smallest aperture (diameter) telescope that will just resolve the two stars? (1 nm = 10^-9 m)

A) 8.5 cm
B) 4.2 cm
C) 6.1 cm
D) 3.0 cm