Question 1

A soap bubble (n = 1.35) is floating in air. If the thickness of the bubble wall is 115 nm, what visible light wavelength is most strongly reflected?

Accepted Answer

621 nm (red)

Question 2

A film of index of refraction n1 coats a surface with index of refraction n2. When n1 2, the condition for destructive interference for reflected monochromatic light of wavelength λ in air is

Accepted Answer

A)    . 
B)    . 
C)    . 
D)    . 
E)    . 
A)    . 
B)    . 
C)    . 
D)    . 
E)    . D

Question 3

When the adjustable mirror on the Michelson interferometer is moved 20 wavelengths, how many fringe pattern shifts would be counted?

Accepted Answer

A) 5 
B) 10 
C) 20 
D) 40 
E) 80 
A) 5 
B) 10 
C) 20 
D) 40 
E) 80 E

Question 4

Bright and dark fringes are seen on a screen when light from a single source reaches two narrow slits a short distance apart. Each bright fringe will shift to the location of the adjacent bright fringe if a thin film is placed in front of one of the slits. The minimum width of this film must be

Accepted Answer

A)    . 
B)    . 
C)    . 
D)    . 
E)    . 
A)    . 
B)    . 
C)    . 
D)    . 
E)    .

Question 5

The large space telescope that has been placed into an Earth orbit has an aperture diameter of 2.40 meters. What angular resolution will this telescope achieve for visible light of wavelength λ = 4.80 × 10−7 m?

Accepted Answer

A) 2.44 × 10−7 rads 
B) 2.44 × 10−4 rads 
C) 2.44 × 10−3 rads 
D) 1.22 × 10−6 rads 
E) 2.00 × 10−6 rads 
A) 2.44 × 10−7 rads 
B) 2.44 × 10−4 rads 
C) 2.44 × 10−3 rads 
D) 1.22 × 10−6 rads 
E) 2.00 × 10−6 rads

Question 6

A ruby laser beam (λ = 694.3 nm) is sent outwards from a 2.7-m diameter telescope to the Moon, 384,000 km away. What is the radius of the big red spot on the Moon?

Accepted Answer

A) 500 m 
B) 250 m 
C) 120 m 
D) 1.0 km 
E) 2.7 km 
A) 500 m 
B) 250 m 
C) 120 m 
D) 1.0 km 
E) 2.7 km

Question 7

Monochromatic light (λ = 500 nm) is incident on a soap bubble (n = 1.4) that is 50 mm thick. What is the change of phase of the light reflected from the front surface?

Accepted Answer

A) 0 
B) 180° 
C) λ/2 
D) π/2 
E) 55° 
A) 0 
B) 180° 
C) λ/2 
D) π/2 
E) 55°

Question 8

In an X-ray diffraction experiment using X-rays of λ = 0.500 × 10−10 m, a first-order maximum occurred at 5.00°. Find the crystal plane spacing.

Accepted Answer

A) 2.87 × 10−10 m 
B) 1.36 × 10−10 m 
C) 6.24 × 10−9 m 
D) 1.93 × 10−9 m 
E) 5.74 × 10−9 m 
A) 2.87 × 10−10 m 
B) 1.36 × 10−10 m 
C) 6.24 × 10−9 m 
D) 1.93 × 10−9 m 
E) 5.74 × 10−9 m

Question 9

What, approximately, are the dimensions of the smallest object on Earth that the astronauts can resolve by eye at 200 km height from the space shuttle? Assume λ = 500 nm light and a pupil diameter D = 0.50 cm. Assume eye fluid has an average n = 1.33.

Accepted Answer

A) 150 m 
B) 100 m 
C) 250 m 
D) 25 m 
E) 18 m 
A) 150 m 
B) 100 m 
C) 250 m 
D) 25 m 
E) 18 m

Question 10

A beam of X-rays of different frequencies is reflected at 10 degrees off a crystal of interatomic spacing 0.2 nm. Which X-ray wavelength is preferentially reflected?

Accepted Answer

A) 0.0943 nm 
B) 0.139 nm 
C) 0.0695 nm 
D) 1.02 × 10−10 m 
E) 3.47 × 10−11 m 
A) 0.0943 nm 
B) 0.139 nm 
C) 0.0695 nm 
D) 1.02 × 10−10 m 
E) 3.47 × 10−11 m

Question 11

Monochromatic light (λ = 500 nm) is incident on a soap bubble (n = 1.4) that is 500-nm thick. Calculate the change of phase of the light that penetrates the front surface, reflects from the second surface, and emerges through the first surface as an angle between 0° and 360°?

Accepted Answer

A) 280° 
B) 160° 
C) 220° 
D) 100° 
E) 290° 
A) 280° 
B) 160° 
C) 220° 
D) 100° 
E) 290°

Question 12

Bright and dark fringes are seen on a screen when light from a single source reaches two narrow slits a short distance apart. The locations of bright and dark fringes can be interchanged if a thin film is placed in front of one of the slits. The minimum width of this film must be

Accepted Answer

A)    . 
B)    . 
C)    . 
D)    . 
E)    . 
A)    . 
B)    . 
C)    . 
D)    . 
E)    .

Question 13

The hydrogen spectrum has a red line at 656 nm, and a blue line at 434 nm. What is the first order angular separation between the two spectral lines obtained with a diffraction grating with 5000 rulings/cm?

Accepted Answer

A) 7.7° 
B) 16.6° 
C) 6.6° 
D) 3.2° 
E) 19.2° 
A) 7.7° 
B) 16.6° 
C) 6.6° 
D) 3.2° 
E) 19.2°

Question 14

A radar installation operates at 9000 MHz with an antenna (dish) that is 15 meters across. Determine the maximum distance (in kilometers) for which this system can distinguish two aircraft 100 meters apart.

Accepted Answer

A) 7.4 km 
B) 370 km 
C) 3700 m 
D) 37 km 
E) 740 km 
A) 7.4 km 
B) 370 km 
C) 3700 m 
D) 37 km 
E) 740 km

Question 15

A helium-neon laser (λ = 632.8 nm) is used to calibrate a diffraction grating. If the first-order maximum occurs at 20.5°, what is the line spacing, d?

Accepted Answer

A) 1.81 × 10−6 m 
B) 1.00 × 10−5 m 
C) 1.00 × 10−4 m 
D) 1.31 × 10−6 m 
E) 6.76 × 10−7 m 
A) 1.81 × 10−6 m 
B) 1.00 × 10−5 m 
C) 1.00 × 10−4 m 
D) 1.31 × 10−6 m 
E) 6.76 × 10−7 m

Question 16

A binary star system in the constellation Orion has an angular separation between the two stars of 1.2 × 10−5 radians. If λ = 5 × 10−7 m, what is the smallest-aperture (diameter) telescope that may be used to resolve the two stars?

Accepted Answer

A) 10 cm 
B) 5 cm 
C) 50 cm 
D) 1 m 
E) 4 cm 
A) 10 cm 
B) 5 cm 
C) 50 cm 
D) 1 m 
E) 4 cm

Question 17

A thin sheet of plastic (n = 1.60) is inserted between two panes of glass to reduce infrared (λ = 700 nm) losses. What thickness (in nm) is necessary to produce constructive interference in the reflected infrared radiation?

Accepted Answer

A) 218 
B) 109 
C) 55 
D) 318 
E) 443 
A) 218 
B) 109 
C) 55 
D) 318 
E) 443

Question 18

A film of index of refraction n1 coats a surface with index of refraction n2. When n1 > n2, the condition for destructive interference for reflected monochromatic light of wavelength λ in air is

Accepted Answer

A)    . 
B)    . 
C)    . 
D)    . 
E)    . 
A)    . 
B)    . 
C)    . 
D)    . 
E)    .

Question 19

White light is spread out into spectral hues by a diffraction grating. If the grating has 1000 lines per cm, at what angle will red light (λ = 640 nm) appear in first order?

Accepted Answer

A) 14.7° 
B) 7.35° 
C) 17.7° 
D) 3.67° 
E) 1.84° 
A) 14.7° 
B) 7.35° 
C) 17.7° 
D) 3.67° 
E) 1.84°

Question 20

A film of index of refraction n1 coats a surface with index of refraction n2. When n1 2, the condition for constructive interference for reflected monochromatic light of wavelength λ in air is

Accepted Answer

A)    . 
B)    . 
C)    . 
D)    . 
E)    . 
A)    . 
B)    . 
C)    . 
D)    . 
E)    .

Exam 36: Applications of the Wave Model

A soap bubble (n = 1.35) is floating in air. If the thickness of the bubble wall is 115 nm, what visible light wavelength is most strongly reflected?

A film of index of refraction n1 coats a surface with index of refraction n2. When n1 < n2, the condition for destructive interference for reflected monochromatic light of wavelength λ in air is

When the adjustable mirror on the Michelson interferometer is moved 20 wavelengths, how many fringe pattern shifts would be counted?

Bright and dark fringes are seen on a screen when light from a single source reaches two narrow slits a short distance apart. Each bright fringe will shift to the location of the adjacent bright fringe if a thin film is placed in front of one of the slits. The minimum width of this film must be

The large space telescope that has been placed into an Earth orbit has an aperture diameter of 2.40 meters. What angular resolution will this telescope achieve for visible light of wavelength λ = 4.80 × 10−7 m?

A ruby laser beam (λ = 694.3 nm) is sent outwards from a 2.7-m diameter telescope to the Moon, 384,000 km away. What is the radius of the big red spot on the Moon?

Monochromatic light (λ = 500 nm) is incident on a soap bubble (n = 1.4) that is 50 mm thick. What is the change of phase of the light reflected from the front surface?

In an X-ray diffraction experiment using X-rays of λ = 0.500 × 10−10 m, a first-order maximum occurred at 5.00°. Find the crystal plane spacing.

What, approximately, are the dimensions of the smallest object on Earth that the astronauts can resolve by eye at 200 km height from the space shuttle? Assume λ = 500 nm light and a pupil diameter D = 0.50 cm. Assume eye fluid has an average n = 1.33.

A beam of X-rays of different frequencies is reflected at 10 degrees off a crystal of interatomic spacing 0.2 nm. Which X-ray wavelength is preferentially reflected?

Monochromatic light (λ = 500 nm) is incident on a soap bubble (n = 1.4) that is 500-nm thick. Calculate the change of phase of the light that penetrates the front surface, reflects from the second surface, and emerges through the first surface as an angle between 0° and 360°?

Bright and dark fringes are seen on a screen when light from a single source reaches two narrow slits a short distance apart. The locations of bright and dark fringes can be interchanged if a thin film is placed in front of one of the slits. The minimum width of this film must be

The hydrogen spectrum has a red line at 656 nm, and a blue line at 434 nm. What is the first order angular separation between the two spectral lines obtained with a diffraction grating with 5000 rulings/cm?

A radar installation operates at 9000 MHz with an antenna (dish) that is 15 meters across. Determine the maximum distance (in kilometers) for which this system can distinguish two aircraft 100 meters apart.

A helium-neon laser (λ = 632.8 nm) is used to calibrate a diffraction grating. If the first-order maximum occurs at 20.5°, what is the line spacing, d?

A binary star system in the constellation Orion has an angular separation between the two stars of 1.2 × 10−5 radians. If λ = 5 × 10−7 m, what is the smallest-aperture (diameter) telescope that may be used to resolve the two stars?

A thin sheet of plastic (n = 1.60) is inserted between two panes of glass to reduce infrared (λ = 700 nm) losses. What thickness (in nm) is necessary to produce constructive interference in the reflected infrared radiation?

A film of index of refraction n1 coats a surface with index of refraction n2. When n1 > n2, the condition for destructive interference for reflected monochromatic light of wavelength λ in air is

White light is spread out into spectral hues by a diffraction grating. If the grating has 1000 lines per cm, at what angle will red light (λ = 640 nm) appear in first order?

A film of index of refraction n1 coats a surface with index of refraction n2. When n1 < n2, the condition for constructive interference for reflected monochromatic light of wavelength λ in air is

Getting Started

One-Dimensional Motion

Vectors

Two- and Three-Dimensional Motion

Newtons Laws of Motion

Applications of Newtons Laws of Motion

Gravity

Conservation of Energy

Energy in Nonisolated Systems

Systems of Particles and Conservation of Momentum

Collisions

Rotation I: Kinematics and Dynamics

Rotation II: a Conservation Approach

Static Equilibrium, Elasticity, and Fracture

Fluids

Oscillations

Traveling Waves

Superposition and Standing Waves

Temperature, Thermal Expansion, and Gas Laws

Kinetic Theory of Gases

Heat and the First Law of Thermodynamics

Entropy and the Second Law of Thermodynamics

Electric Forces

Electric Fields

Gausss Law

Electric Potential

Capacitors and Batteries

Current and Resistance

Direct Current Dc Circuits

Magnetic Fields and Forces

Gausss Law for Magnetism and Amperes Law

Faradays Law of Induction

Inductors and Ac Circuits

Maxwells Equations and Electromagnetic Waves

Diffraction and Interference

Reflection and Images Formed by Reflection

Refraction and Images Formed by Refraction

Relativity

Filters

A film of index of refraction n₁ coats a surface with index of refraction n₂. When n₁< n₂, the condition for destructive interference for reflected monochromatic light of wavelength λ in air is

A film of index of refraction n₁ coats a surface with index of refraction n₂. When n₁ > n₂, the condition for destructive interference for reflected monochromatic light of wavelength λ in air is

A film of index of refraction n₁ coats a surface with index of refraction n₂. When n₁ < n₂, the condition for constructive interference for reflected monochromatic light of wavelength λ in air is