Question 1

Light reflects off the surface of Lake Superior. What phase shift does it undergo?
A) 0°
B) 90°
C) 180°
D) 270°
E) It does not undergo any phase shift.

Accepted Answer

When light reflects off a highly reflective surface, such as water, it undergoes a phase shift of 180°.

Question 2

If a diffraction grating is heated (without damaging it) and therefore expands, what happens to the angular location of the first-order maximum?
A) It moves toward the centerline.
B) It moves away from the centerline.
C) It doesn't change.

Accepted Answer

The angular location of the first-order maximum is given by the equation: sinθ = λ/d, where θ is the angle between the incident beam and the direction of the diffracted beam, λ is the wavelength of the light, and d is the spacing between the lines of the grating. If the grating expands due to heating, the spacing d increases, which means that sinθ decreases. Since sinθ is proportional to the angle θ, this means that the angle of the first-order maximum decreases (moves toward the centerline). Therefore, choice A is the best answer.

Question 3

Light of wavelength 550 nm in air is found to travel at 1.96 × 10⁸ m/s in a certain liquid. What are the frequency and wavelength of the light in this liquid? (c = 3.0 × 10⁸ m/s)

Accepted Answer

The answer of Light of wavelength 550 nm in air...

Question 4

When a beam of light that is traveling in air is reflected by a glass surface, there is
A) a 90° phase change in the reflected beam.
B) no phase change in the reflected beam.
C) a 180° phase change in the reflected beam.
D) a 60° phase change in the reflected beam.
E) a 45° phase change in the reflected beam.

Accepted Answer

When a beam of light traveling in air is reflected by a glass surface, there is a 180° phase change in the reflected beam. This is because when light passes through a denser medium, such as glass, the wave undergoes a phase change of 180° upon reflection due to the reversal of the electric and magnetic fields.

Question 5

Red light with a wavelength of 650 nm travels from air into a liquid with an index of 1.33. What are the frequency and wavelength of the light in the liquid? (c = 3.0 × 10⁸ m/s)

Accepted Answer

The answer of Red light with a wavelength of 650...

Question 6

Light of wavelength 550 nm in air is found to travel at 1.96 × 10⁸ m/s in a certain liquid. (c = 3.0 × 10⁸ m/s) (a) What is the index of refraction of this liquid? (b) What is the frequency of the light in air?

Accepted Answer

The answer of Light of wavelength 550 nm in air...

Question 7

When a beam of light that is traveling in glass strikes an air boundary at the surface of the glass, there is
A) a 90° phase change in the reflected beam.
B) no phase change in the reflected beam.
C) a 180° phase change in the reflected beam.
D) a 60° phase change in the reflected beam.
E) a 45° phase change in the reflected beam.

Accepted Answer

The answer of When a beam of light that is...

Question 8

The colors on an oil slick are caused by reflection and
A) diffraction.
B) interference.
C) refraction.
D) polarization.
E) ionization.

Accepted Answer

The colors on an oil slick are caused by interference, specifically the interference of light waves reflecting off the surface of the oil and the underlying water. This creates a pattern of light and dark areas that we perceive as colors.

Question 9

Light having a frequency in vacuum of 6.0 × 10¹⁴ Hz enters a liquid of refractive index 2.0. What is the frequency of the light in this liquid? (c = 3.0 × 10⁸ m/s) A) 12 × 10¹⁴ Hz B) 6.0 × 10¹⁴ Hz C) 3.0 × 10¹⁴ Hz D) 1.5 × 10¹⁴ Hz E) 2.0 × 10¹⁴ Hz

Accepted Answer

The frequency of light does not change when it enters a medium with a different refractive index. The change in speed and wavelength does not affect the frequency.

Question 10

When a beam of light, originally traveling in air, enters a piece of glass having an index of refraction of 3/2, its speed
A) increases by a factor of 3/2.
B) is reduced to 2/3 its original value.
C) is unaffected.

Accepted Answer

The speed of light in a medium with index of refraction n is given by v = c/n, where c is the speed of light in vacuum or air. Thus, when light enters a glass with index of refraction 3/2 from air, its speed is reduced to v' = c/(3/2) = 2c/3, which is 2/3 of its original speed in air. Therefore, choice B is correct.

Question 11

Light in a frozen block of ice reflects off the ice-air interface at the surface of the block. What phase shift does it undergo?
A) 0°
B) 90°
C) 180°
D) 270°
E) It does not undergo any phase shift.

Accepted Answer

The answer of Light in a frozen block of ice...

Question 12

Which of the following changes would increase the separation between the bright fringes in the diffraction pattern formed by a diffraction grating?
A) Increase the wavelength of the light used.
B) Increase the separation between the slits.
C) Immerse the apparatus in water.
D) All of these.
E) None of these.

Accepted Answer

Increasing the wavelength of the light used increases the separation between the bright fringes in a diffraction pattern, according to the diffraction grating equation.

Question 13

The index of refraction of a certain glass is measured to be 1.5. What is the speed of light in that glass? (c = 3.0 × 10⁸ m/s) A) 1.0 × 10⁸ m/s B) 2.0 × 10⁸ m/s C) 3.0 × 10⁸ m/s D) 4.0 × 10⁸ m/s E) 5.0 × 10⁸ m/s

Accepted Answer

The speed of light in a medium is given by v = c/n, where c is the speed of light in vacuum and n is the refractive index of the medium. Therefore, the speed of light in the given glass is v = (3.0 × 10^8 m/s) / 1.5 = 2.0 × 10^8 m/s, which corresponds to choice B.

Question 14

If a metal sheet containing a tiny hole is heated (without damaging it) and therefore expands, what happens to the angular location of the first-order diffraction maximum?
A) It moves toward the centerline.
B) It moves away from the centerline.
C) It doesn't change.

Accepted Answer

The answer of If a metal sheet containing a tiny...

Question 15

When a beam of light, originally traveling in air, enters a piece of glass having an index of refraction of 3/2, its wavelength
A) increases by a factor of 3/2.
B) is reduced to 2/3 its original value.
C) is unaffected.

Accepted Answer

The wavelength of the light is reduced as it enters the medium with a higher index of refraction. The change in wavelength is determined by the ratio of the indices of refraction, which is 3/2 in this case. So the new wavelength in the glass will be (2/3) times the original wavelength in air.

Question 16

When a light wave enters into a medium of different refractive index,
A) only its speed and frequency change.
B) only its speed and wavelength change.
C) only its frequency and wavelength change.
D) its speed, frequency, and wavelength change.

Accepted Answer

When a light wave enters a medium of different refractive index, its speed and wavelength change, but its frequency remains constant because frequency is determined by the source of the light and does not change when light enters a different medium.

Question 17

Light having a speed in vacuum of 3.0 × 10⁸ m/s enters a liquid of refractive index 2.0. In this liquid, its speed will be A) 6.0 × 10⁸ m/s B) 3.0 × 10⁸ m/s C) 1.5 × 10⁸ m/s D) 0.75 × 10⁸ m/s E) 0.67 × 10⁸ m/s

Accepted Answer

The speed of light in a medium is given by v = c/n, where c is the speed of light in vacuum and n is the refractive index of the medium. In this case, the speed of light in the liquid is v = (3.0 × 10^8 m/s) / 2.0 = 1.5 × 10^8 m/s. So the answer is choice C).

Question 18

Light of the same wavelength passes through two diffraction gratings. One grating has 4000 lines/cm, and the other one has 6000 lines/cm. Which grating will spread the light through a larger angle in the first-order pattern?
A) the 4000-line grating
B) the 6000-line grating
C) Both gratings spread the light the same.

Accepted Answer

The angle of diffraction is given by the equation sinθ = mλ/d, where θ is the angle of diffraction, m is the order of diffraction, λ is the wavelength of light, and d is the spacing between adjacent lines on the grating. Since the wavelength of light is the same, the angle of diffraction will depend on the spacing between the lines on the grating. The grating with the smaller spacing (i.e. more lines per cm) will produce a larger angle of diffraction. Therefore, the 6000-line grating will spread the light through a larger angle in the first-order pattern.

Question 19

When a beam of light, originally traveling in air, enters a piece of glass having an index of refraction of 3/2, its frequency
A) increases by a factor of 3/2.
B) is reduced to 2/3 its original value.
C) is unaffected.

Accepted Answer

The frequency of light is not affected by its change in medium. Therefore, when light travels from air to glass, its frequency remains the same regardless of the glass's index of refraction.

Question 20

The speed of light in a certain material is measured to be 2.2 × 10⁸ m/s. What is the index of refraction of this material? (c = 3.0 × 10⁸ m/s) A) 1.1 B) 1.2 C) 1.4 D) 1.6 E) 1.8

Accepted Answer

The index of refraction (n) of a material is given by the ratio of the speed of light in a vacuum (c) to the speed of light in the material (v): n = c / v We are given the speed of light in the material (v) as 2.2 × 10⁸ m/s. Substituting this into the equation above, we get: n = c / v = 3.0 × 10⁸ m/s / 2.2 × 10⁸ m/s n = 1.36 Therefore, the index of refraction of this material is approximately 1.4. The closest answer choice is C.

Quiz 17: Wave Optics

Light reflects off the surface of Lake Superior. What phase shift does it undergo?

If a diffraction grating is heated (without damaging it) and therefore expands, what happens to the angular location of the first-order maximum?

Light of wavelength 550 nm in air is found to travel at 1.96 × 108 m/s in a certain liquid. What are the frequency and wavelength of the light in this liquid? (c = 3.0 × 108 m/s)

When a beam of light that is traveling in air is reflected by a glass surface, there is

Red light with a wavelength of 650 nm travels from air into a liquid with an index of 1.33. What are the frequency and wavelength of the light in the liquid? (c = 3.0 × 108 m/s)

Light of wavelength 550 nm in air is found to travel at 1.96 × 108 m/s in a certain liquid. (c = 3.0 × 108 m/s) (a) What is the index of refraction of this liquid? (b) What is the frequency of the light in air?

When a beam of light that is traveling in glass strikes an air boundary at the surface of the glass, there is

The colors on an oil slick are caused by reflection and

Light having a frequency in vacuum of 6.0 × 1014 Hz enters a liquid of refractive index 2.0. What is the frequency of the light in this liquid? (c = 3.0 × 108 m/s)

When a beam of light, originally traveling in air, enters a piece of glass having an index of refraction of 3/2, its speed

Light in a frozen block of ice reflects off the ice-air interface at the surface of the block. What phase shift does it undergo?

Which of the following changes would increase the separation between the bright fringes in the diffraction pattern formed by a diffraction grating?

The index of refraction of a certain glass is measured to be 1.5. What is the speed of light in that glass? (c = 3.0 × 108 m/s)

If a metal sheet containing a tiny hole is heated (without damaging it) and therefore expands, what happens to the angular location of the first-order diffraction maximum?

When a beam of light, originally traveling in air, enters a piece of glass having an index of refraction of 3/2, its wavelength

When a light wave enters into a medium of different refractive index,

Light having a speed in vacuum of 3.0 × 108 m/s enters a liquid of refractive index 2.0. In this liquid, its speed will be

Light of the same wavelength passes through two diffraction gratings. One grating has 4000 lines/cm, and the other one has 6000 lines/cm. Which grating will spread the light through a larger angle in the first-order pattern?

When a beam of light, originally traveling in air, enters a piece of glass having an index of refraction of 3/2, its frequency

The speed of light in a certain material is measured to be 2.2 × 108 m/s. What is the index of refraction of this material? (c = 3.0 × 108 m/s)

Light of wavelength 550 nm in air is found to travel at 1.96 × 10⁸ m/s in a certain liquid. What are the frequency and wavelength of the light in this liquid? (c = 3.0 × 10⁸ m/s)

Red light with a wavelength of 650 nm travels from air into a liquid with an index of 1.33. What are the frequency and wavelength of the light in the liquid? (c = 3.0 × 10⁸ m/s)

Light of wavelength 550 nm in air is found to travel at 1.96 × 10⁸ m/s in a certain liquid. (c = 3.0 × 10⁸ m/s) (a) What is the index of refraction of this liquid? (b) What is the frequency of the light in air?

Light having a frequency in vacuum of 6.0 × 10¹⁴ Hz enters a liquid of refractive index 2.0. What is the frequency of the light in this liquid? (c = 3.0 × 10⁸ m/s)

The index of refraction of a certain glass is measured to be 1.5. What is the speed of light in that glass? (c = 3.0 × 10⁸ m/s)

Light having a speed in vacuum of 3.0 × 10⁸ m/s enters a liquid of refractive index 2.0. In this liquid, its speed will be

The speed of light in a certain material is measured to be 2.2 × 10⁸ m/s. What is the index of refraction of this material? (c = 3.0 × 10⁸ m/s)