Question 1

The dispersion of a diffraction grating indicates:

Accepted Answer

A)   the resolution of the grating
B)   the separation of lines of the same order
C)   the number of rulings in the grating
D)   the width of the lines
E)   the separation of lines of different order for the same wavelength

Question 2

The resolving power of a telescope can be increased by:

Accepted Answer

A)   increasing the objective focal length and decreasing the eyepiece focal length
B)   increasing the lens diameters
C)   decreasing the lens diameters
D)   inserting a correction lens between objective and eyepiece
E)   none of the above

Question 3

A diffraction pattern is produced on a viewing screen by illuminating a long narrow slit with light of wavelength  λ\lambdaλ . If  λ\lambdaλ  is increased and no other changes are made:

Accepted Answer

A)   the intensity at the center of the pattern decreases and the pattern expands away from the bright center
B)   the intensity at the center of the pattern increases and the pattern contracts toward the bright center
C)   the intensity at the center of the pattern does not change and the pattern expands away from the bright center
D)   the intensity at the center of the pattern does not change and the pattern contracts toward the bright center
E)   neither the intensity at the center of the pattern nor the pattern itself change

Question 4

If white light is incident on a diffraction grating:

Accepted Answer

A)   the first order lines for all visible wavelengths occur at smaller diffraction angles than any of the second order lines
B)   some first order lines overlap the second order lines if the ruling separation is small but do not if it is large
C)   some first order lines overlap second order lines if the ruling separation is large but do not if it is small
D)   some first order lines overlap second order lines no matter what the ruling separation
E)   first and second order lines have the same range of diffraction angles

Question 5

An x-ray beam of wavelength 3 *10-11 m is incident on a calcite crystal of lattice spacing 0.3 nm. The smallest angle between crystal planes and the x-ray beam which will result in constructive interference is:

Accepted Answer

A)   2.87°
B)   5.73°
C)   11.63°
D)   23.27°
E)   none of these

Question 6

In the equation d sin θ	hetaθ  = m λ\lambdaλ for the lines of a diffratction grating d is:

Accepted Answer

A)   the number of slits
B)   the slit width
C)   the slit separation
D)   the order of the line
E)   the index of refraction

Question 7

The widths of the lines produced by monochromatic light falling on a diffraction grating can be reduced by:

Accepted Answer

A)   increasing the wavelength of the light
B)   increasing the number of rulings without changing their spacing
C)   decreasing the spacing between adjacent rulings without changing the number of rulings
D)   decreasing both the wavelength and the spacing between rulings by the same factor
E)   increasing the number of rulings and decreasing their spacing so the length of the grating remains the same

Question 8

Diffraction plays an important role in which of the following phenomena?

Accepted Answer

A)   The sun appears as a disk rather than a point to the naked eye
B)   Light is bent as it passes through a glass prism
C)   A cheerleader yells through a megaphone
D)   A farsighted person uses eyeglasses of positive focal length
E)   A thin soap film exhibits colors when illuminated with white light

Question 9

In a double-slit diffraction experiment the number of interference fringes within the central diffraction maximum can be increased by:

Accepted Answer

A)   increasing the wavelength
B)   decreasing the wavelength
C)   increasing the slit separation
D)   decreasing the slit width
E)   increasing the slit width

Question 10

The diagram shows a single slit with the direction to a point P on a distant screen shown. At P, the pattern has its second minimum (from its central maximum) . If X and Y are the edges of the slit, what is the path length difference (PX)  - (PY) ?

Accepted Answer

A)    λ\lambdaλ /2
B)    λ\lambdaλ 
C)   3 λ\lambdaλ /2
D)   2 λ\lambdaλ 
E)   5 λ\lambdaλ /2

Question 11

When the atmosphere is not quite clear, one may sometimes see colored circles concentric with the Sun or the Moon. These are generally not more than a few diameters of the Sun or Moon and invariably the innermost ring is blue. The explanation for this phenomena involves:

Accepted Answer

A)   reflection
B)   refraction
C)   interference
D)   diffraction
E)   Doppler effect

Question 12

At the second minimum adjacent to the central maximum of a single-slit diffraction pattern the Huygens wavelet from the top of the slit is 180 °\degree°  out of phase with the wavelet from:

Accepted Answer

A)   a point one-fourth of the slit width from the top
B)   the midpoint of the slit
C)   a point one-fourth of the slit width from the bottom of the slit
D)   the bottom of the slit
E)   none of these

Question 13

Monochromatic plane waves of light are incident normally on a single slit. Which one of the five figures below correctly shows the diffraction pattern observed on a distant screen?

Accepted Answer

A)   I
B)   II
C)   III
D)   IV
E)   V

Question 14

When light of a certain wavelength is incident normally on a certain diffraction grating the line of order 1 is at a diffraction angle of 25  °\degree° . The diffraction angle for the second order line is:

Accepted Answer

A)   25  °\degree° 
B)   42  °\degree° 
C)   50  °\degree° 
D)   58  °\degree° 
E)   75  °\degree°

Question 15

Two wavelengths, 800 nm and 600 nm, are used separately in single-slit diffraction experiments. The diagram shows the intensities on a far-away viewing screen as function of the angle made by the rays with the straight-ahead direction. If both wavelengths are then used simultaneously, at which angle is the light on the screen purely 800-nm light?

Accepted Answer

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

Question 16

If we increase the wavelength of the light used to form a double-slit diffraction pattern:

Accepted Answer

A)   the width of the central diffraction peak increases and the number of bright fringes within the peak increases
B)   the width of the central diffraction peak increases and the number of bright fringes with the peak decreases
C)   the width of the central diffraction peak decreases and the number of bright fringes within the peak increases
D)   the width of the central diffraction peak decreases and the number of bright fringes within the peak decreases
E)   the width of the central diffraction peak increases and the number of bright fringes within the peak stays the same

Question 17

A light spectrum is formed on a screen using a diffraction grating. The entire apparatus (source, grating and screen)  is now immersed in a liquid of index 1.33. As a result, the pattern on the screen:

Accepted Answer

A)   remains the same
B)   spreads out
C)   crowds together
D)   becomes reversed, with the previously blue end becoming red
E)   disappears because the index isn't an integer

Question 18

Light of wavelength  λ\lambdaλ  is normally incident on a diffraction grating G. On the screen S, the central line is at P and the first order line is at Q, as shown. The distance between adjacent slits in the grating is:

Accepted Answer

A)   3 λ\lambdaλ /5
B)   3 λ\lambdaλ /4
C)   4 λ\lambdaλ /5
D)   5 λ\lambdaλ /4
E)   5 λ\lambdaλ /3

Question 19

In the equation  ϕ\phiϕ  = (2 π\piπ a/ λ\lambdaλ )  sin  θ	hetaθ for single-slit diffraction,  ϕ\phiϕ  is:

Accepted Answer

A)   the angle to the first minimum
B)   the angle to the second maximum
C)   the phase angle between the extreme rays
D)   N π\piπ  where N is an integer
E)   (N + 1/2)  π\piπ  where N is an integer

Question 20

When 450-nm light is incident normally on a certain double-slit system the number of interference maxima within the central diffraction maximum is 5. When 900-nm light is incident on the same slit system the number is:

Accepted Answer

A)   2
B)   3
C)   5
D)   9
E)   10

Exam 36: Diffraction

When light of a certain wavelength is incident normally on a certain diffraction grating the line of order 1 is at a diffraction angle of 25 $\degree$ . The diffraction angle for the second order line is:

Correct Answer
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Correct Answer
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If we increase the wavelength of the light used to form a double-slit diffraction pattern:

Correct Answer
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Correct Answer
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If white light is incident on a diffraction grating:

Correct Answer
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At the second minimum adjacent to the central maximum of a single-slit diffraction pattern the Huygens wavelet from the top of the slit is 180 $\degree$ out of phase with the wavelet from:

Correct Answer
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In the equation $\phi$ = (2 $\pi$ a/ $\lambda$ ) sin $\theta$ for single-slit diffraction, $\phi$ is:

Correct Answer
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The resolving power of a telescope can be increased by:

Correct Answer
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Diffraction plays an important role in which of the following phenomena?

Correct Answer
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Correct Answer
verified

The dispersion of a diffraction grating indicates:

Correct Answer
verified

In the equation d sin $\theta$ = m $\lambda$ for the lines of a diffratction grating d is:

Correct Answer
verified

The widths of the lines produced by monochromatic light falling on a diffraction grating can be reduced by:

Correct Answer
verified

A light spectrum is formed on a screen using a diffraction grating. The entire apparatus (source, grating and screen) is now immersed in a liquid of index 1.33. As a result, the pattern on the screen:

Correct Answer
verified

When 450-nm light is incident normally on a certain double-slit system the number of interference maxima within the central diffraction maximum is 5. When 900-nm light is incident on the same slit system the number is:

Correct Answer
verified

When the atmosphere is not quite clear, one may sometimes see colored circles concentric with the Sun or the Moon. These are generally not more than a few diameters of the Sun or Moon and invariably the innermost ring is blue. The explanation for this phenomena involves:

Correct Answer
verified

An x-ray beam of wavelength 3 *10^-¹¹ m is incident on a calcite crystal of lattice spacing 0.3 nm. The smallest angle between crystal planes and the x-ray beam which will result in constructive interference is:

Correct Answer
verified

Correct Answer
verified

A diffraction pattern is produced on a viewing screen by illuminating a long narrow slit with light of wavelength $\lambda$ . If $\lambda$ is increased and no other changes are made:

Correct Answer
verified

In a double-slit diffraction experiment the number of interference fringes within the central diffraction maximum can be increased by:

Correct Answer
verified

Exam 36: Diffraction

When light of a certain wavelength is incident normally on a certain diffraction grating the line of order 1 is at a diffraction angle of 25 °\degree° . The diffraction angle for the second order line is:

Correct AnswerverifiedShow Answer

The diagram shows a single slit with the direction to a point P on a distant screen shown. At P, the pattern has its second minimum (from its central maximum) . If X and Y are the edges of the slit, what is the path length difference (PX) - (PY) ?

Correct AnswerverifiedShow Answer

If we increase the wavelength of the light used to form a double-slit diffraction pattern:

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

If white light is incident on a diffraction grating:

Correct AnswerverifiedShow Answer

At the second minimum adjacent to the central maximum of a single-slit diffraction pattern the Huygens wavelet from the top of the slit is 180 °\degree° out of phase with the wavelet from:

Correct AnswerverifiedShow Answer

In the equation ϕ\phiϕ = (2 π\piπ a/ λ\lambdaλ ) sin θ\thetaθ for single-slit diffraction, ϕ\phiϕ is:

Correct AnswerverifiedShow Answer

The resolving power of a telescope can be increased by:

Correct AnswerverifiedShow Answer

Diffraction plays an important role in which of the following phenomena?

Correct AnswerverifiedShow Answer

Monochromatic plane waves of light are incident normally on a single slit. Which one of the five figures below correctly shows the diffraction pattern observed on a distant screen?

Correct AnswerverifiedShow Answer

The dispersion of a diffraction grating indicates:

Correct AnswerverifiedShow Answer

In the equation d sin θ\thetaθ = m λ\lambdaλ for the lines of a diffratction grating d is:

Correct AnswerverifiedShow Answer

The widths of the lines produced by monochromatic light falling on a diffraction grating can be reduced by:

Correct AnswerverifiedShow Answer

A light spectrum is formed on a screen using a diffraction grating. The entire apparatus (source, grating and screen) is now immersed in a liquid of index 1.33. As a result, the pattern on the screen:

Correct AnswerverifiedShow Answer

When 450-nm light is incident normally on a certain double-slit system the number of interference maxima within the central diffraction maximum is 5. When 900-nm light is incident on the same slit system the number is:

Correct AnswerverifiedShow Answer

When the atmosphere is not quite clear, one may sometimes see colored circles concentric with the Sun or the Moon. These are generally not more than a few diameters of the Sun or Moon and invariably the innermost ring is blue. The explanation for this phenomena involves:

Correct AnswerverifiedShow Answer

An x-ray beam of wavelength 3 *10-11 m is incident on a calcite crystal of lattice spacing 0.3 nm. The smallest angle between crystal planes and the x-ray beam which will result in constructive interference is:

Correct AnswerverifiedShow Answer

Light of wavelength λ\lambdaλ is normally incident on a diffraction grating G. On the screen S, the central line is at P and the first order line is at Q, as shown. The distance between adjacent slits in the grating is:

Correct AnswerverifiedShow Answer

A diffraction pattern is produced on a viewing screen by illuminating a long narrow slit with light of wavelength λ\lambdaλ . If λ\lambdaλ is increased and no other changes are made:

Correct AnswerverifiedShow Answer

In a double-slit diffraction experiment the number of interference fringes within the central diffraction maximum can be increased by:

Correct AnswerverifiedShow Answer

When light of a certain wavelength is incident normally on a certain diffraction grating the line of order 1 is at a diffraction angle of 25 $\degree$ . The diffraction angle for the second order line is:

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

At the second minimum adjacent to the central maximum of a single-slit diffraction pattern the Huygens wavelet from the top of the slit is 180 $\degree$ out of phase with the wavelet from:

Correct Answer
verified

In the equation $\phi$ = (2 $\pi$ a/ $\lambda$ ) sin $\theta$ for single-slit diffraction, $\phi$ is:

Correct Answer
verified

Correct Answer
verified

Correct Answer
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Correct Answer
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Correct Answer
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In the equation d sin $\theta$ = m $\lambda$ for the lines of a diffratction grating d is:

Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
verified

An x-ray beam of wavelength 3 *10^-¹¹ m is incident on a calcite crystal of lattice spacing 0.3 nm. The smallest angle between crystal planes and the x-ray beam which will result in constructive interference is:

Correct Answer
verified

Correct Answer
verified

A diffraction pattern is produced on a viewing screen by illuminating a long narrow slit with light of wavelength $\lambda$ . If $\lambda$ is increased and no other changes are made:

Correct Answer
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Correct Answer
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