Question 1

The electric field of an electromagnetic wave is given by Ey = 25 sin 2.4 × 106 π x - 3.0 × 108t) ) . What is the wavelength of the wave?

Accepted Answer

A)   4.8 × 107 m
B)   2.1 × 10-8 m
C)   2.1 × 10-7 m
D)   8.3 × 10-7 m
E)   7.5 × 10-6 mF) C) and E)
G) B) and C)

Question 2

Ultrafast pulse lasers can emit pulses of the order 10 fs. If each pulse that is 10 fs long and the wavelength of the laser is 500 nm, the number of wavelengths in each pulse is

Accepted Answer

A)   6.
B)   10.
C)   12.
D)   50.
E)   120.F) A) and D)
G) A) and E)

Question 3

Which of the following statements is true?

Accepted Answer

A)   A changing electric field induces a magnetic field.
B)   A changing magnetic field induces an electric field.
C)   Maxwell's equations predict the speed of light.
D)   Maxwell's equations predict that light is made up of oscillating electric and magnetic waves.
E)   All the above statements are true.F) A) and B)
G) A) and C)

Question 4

A common unit of length in astronomy is the parsec, where 1 parsec = 3.26 light years. How many seconds does it take a radio signal to travel one parsec through space?

Accepted Answer

A)   1.03 × 108 s
B)   9.71 × 108 s
C)   9.71 × 107 s
D)   1.72 × 106 s
E)   None of the above.F) C) and E)
G) None of the above

Question 5

A beam of light is propagating in the x direction. The electric-field vector

Accepted Answer

A)   can oscillate in any arbitrary direction in space.
B)   must oscillate in the z direction.
C)   must oscillate in the yz plane.
D)   must oscillate in the x direction.
E)   must have a steady component in the x direction.F) A) and B)
G) A) and C)

Question 6

The speed of ultraviolet radiation in free space compared with the speed of visible radiation in free space is

Accepted Answer

A)   very much greater.
B)   a little greater.
C)   the same.
D)   a little less.
E)   very much less.F) A) and B)
G) D) and E)

Question 7

Which of the following groups is arranged in order of increasing wavelength?

Accepted Answer

A)   infrared, ultraviolet, microwaves
B)   x rays, visible, infrared
C)   gamma rays, ultraviolet, x rays
D)   microwaves, gamma rays, visible
E)   infrared, ultraviolet, gamma raysF) A) and D)
G) A) and C)

Question 8

Ultrafast pulse lasers can emit pulses of the order 10 fs. The length of each pulse that is 10 fs long is

Accepted Answer

A)   1.0 μm.
B)   2.0 μm.
C)   3.0 μm.
D)   9.0 μm.
E)   12.0 μm.F) A) and E)
G) C) and D)

Question 9

An AC voltage is applied across a capacitor. Which figure best represents the magnetic field between the capacitor?

Accepted Answer

A)   1
B)   2
C)   3
D)   4
E)   5F) A) and E)
G) None of the above

Question 10

A 60-W lightbulb emits spherical electromagnetic waves uniformly in all directions. If 50% of the power input to such a lightbulb is emitted as electromagnetic radiation, what is the maximum value of the electric field at a distance of 2.0 m from the lightbulb?

Accepted Answer

A)   43 V/m
B)   0.11 mV/m
C)   21 V/m
D)   60 V/m
E)   30 V/mF) C) and D)
G) A) and D)

Question 11

Earth is about 28,000 light years from the center of the Milky Way Galaxy. If a supernova explosion occurred approximately 14,000 light years away from us and released 2.0 × 1046 J of energy in a sudden burst of light, how much energy would enter one of your pupils? Assume the diameter of a pupil to be about 4 mm. For comparison, our Sun radiates approximately 4 × 1026 J/s.)

Accepted Answer

A)   1.1 J
B)   3.0 × 1023 J
C)   3.5 J
D)   4.6 J
E)   2.2 JF) None of the above
G) D) and E)

Question 12

Which of the following statements is false?

Accepted Answer

A)   Isolated electric charges exist.
B)   Electric field lines diverge from positive charges and converge on negative charges.
C)   The flux of the magnetic-field vector is zero through any closed surface.
D)   Isolated magnetic poles exist.
E)   Changing electric fields induce changing magnetic fields.F) A) and D)
G) B) and C)

Question 13

The frequency of a particular electromagnetic wave is 5.00 x 1014 Hz. What is the energy of an individual photon in that wave?

Accepted Answer

A)   5.00 x 1014 J
B)   3.32 x 10-19 J
C)   6.00 x 10-7 J
D)   2.00 x 10-15 J
E)   5.00 x 10-14 JF) A) and D)
G) A) and C)

Exam 22: Electromagnetic Waves

Which of the following statements is true?

Correct Answer
verified

Ultrafast pulse lasers can emit pulses of the order 10 fs. The length of each pulse that is 10 fs long is

Correct Answer
verified

Which of the following groups is arranged in order of increasing wavelength?

Correct Answer
verified

Which of the following statements is false?

Correct Answer
verified

A 60-W lightbulb emits spherical electromagnetic waves uniformly in all directions. If 50% of the power input to such a lightbulb is emitted as electromagnetic radiation, what is the maximum value of the electric field at a distance of 2.0 m from the lightbulb?

Correct Answer
verified

The electric field of an electromagnetic wave is given by E_y = 25 sin 2.4 × 10⁶ π x - 3.0 × 10⁸t) ) . What is the wavelength of the wave?

Correct Answer
verified

The speed of ultraviolet radiation in free space compared with the speed of visible radiation in free space is

Correct Answer
verified

An AC voltage is applied across a capacitor. Which figure best represents the magnetic field between the capacitor?

Correct Answer
verified

Correct Answer
verified

Ultrafast pulse lasers can emit pulses of the order 10 fs. If each pulse that is 10 fs long and the wavelength of the laser is 500 nm, the number of wavelengths in each pulse is

Correct Answer
verified

A common unit of length in astronomy is the parsec, where 1 parsec = 3.26 light years. How many seconds does it take a radio signal to travel one parsec through space?

Correct Answer
verified

A beam of light is propagating in the x direction. The electric-field vector

Correct Answer
verified

The frequency of a particular electromagnetic wave is 5.00 x 10¹⁴ Hz. What is the energy of an individual photon in that wave?

Correct Answer
verified

Exam 22: Electromagnetic Waves

Which of the following statements is true?

Correct AnswerverifiedShow Answer

Ultrafast pulse lasers can emit pulses of the order 10 fs. The length of each pulse that is 10 fs long is

Correct AnswerverifiedShow Answer

Which of the following groups is arranged in order of increasing wavelength?

Correct AnswerverifiedShow Answer

Which of the following statements is false?

Correct AnswerverifiedShow Answer

A 60-W lightbulb emits spherical electromagnetic waves uniformly in all directions. If 50% of the power input to such a lightbulb is emitted as electromagnetic radiation, what is the maximum value of the electric field at a distance of 2.0 m from the lightbulb?

Correct AnswerverifiedShow Answer

The electric field of an electromagnetic wave is given by Ey = 25 sin 2.4 × 106 π x - 3.0 × 108t) ) . What is the wavelength of the wave?

Correct AnswerverifiedShow Answer

The speed of ultraviolet radiation in free space compared with the speed of visible radiation in free space is

Correct AnswerverifiedShow Answer

An AC voltage is applied across a capacitor. Which figure best represents the magnetic field between the capacitor?

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

Ultrafast pulse lasers can emit pulses of the order 10 fs. If each pulse that is 10 fs long and the wavelength of the laser is 500 nm, the number of wavelengths in each pulse is

Correct AnswerverifiedShow Answer

A common unit of length in astronomy is the parsec, where 1 parsec = 3.26 light years. How many seconds does it take a radio signal to travel one parsec through space?

Correct AnswerverifiedShow Answer

A beam of light is propagating in the x direction. The electric-field vector

Correct AnswerverifiedShow Answer

The frequency of a particular electromagnetic wave is 5.00 x 1014 Hz. What is the energy of an individual photon in that wave?

Correct AnswerverifiedShow Answer

Correct Answer
verified

Correct Answer
verified

Correct Answer
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Correct Answer
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Correct Answer
verified

The electric field of an electromagnetic wave is given by E_y = 25 sin 2.4 × 10⁶ π x - 3.0 × 10⁸t) ) . What is the wavelength of the wave?

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
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Correct Answer
verified

The frequency of a particular electromagnetic wave is 5.00 x 10¹⁴ Hz. What is the energy of an individual photon in that wave?

Correct Answer
verified