Chapter 22: Electromagnetic Waves
- 1.The basic equations for all electromagnetism were developed by
- A.
Newton.
- B.
Gauss.
- C.
Maxwell.
- D.
Hertz.
- 2.An electric field is produced by a
- A.
Constant magnetic field.
- B.
Changing magnetic field.
- C.
Either a constant or a changing magnetic field.
- D.
None of the given answers
- 3.A changing electric field will produce a
- A.
Current.
- B.
Gravitational field.
- C.
Magnetic field.
- D.
None of the given answers
- 4.All electromagnetic waves travel through a vacuum at
- A.
The same speed.
- B.
Speeds that are proportional to their frequency.
- C.
Speeds that are inversely proportional to their frequency.
- D.
None of the given answers
- 5.In a vacuum, the velocity of all electromagnetic waves
- A.
Is zero.
- B.
Is nearly 3 * 10^8 m/s.
- C.
Depends on the frequency.
- D.
Depends on their amplitude.
- 6.Electromagnetic waves can travel through
- A.
Glass.
- B.
Iron.
- C.
Water.
- D.
None of the given answers
- 7.The strength of both the electric and magnetic fields in the radiation field are found to decrease with distance as
- A.
1/r.
- B.
1/r^2.
- C.
1/r^3.
- D.
1/r^4.
- 8.The E and B fields in electromagnetic waves are oriented
- A.
Parallel to the wave's direction of travel, as well as to each other.
- B.
Parallel to the waves direction of travel, and perpendicular to each other.
- C.
Perpendicular to the wave's direction of travel, and parallel to each other.
- D.
Perpendicular to the wave's direction of travel, and also to each other.
- 9.An electromagnetic wave is traveling to the east. At one instant at a given point its E vector points straight up. What is the direction of its B vector?
- A.
North
- B.
Down
- C.
East
- D.
South
- 10.An electromagnetic wave is radiated by a straight wire antenna that is oriented vertically. What should be the orientation of a straight wire receiving antenna? It should be placed
- A.
Vertically.
- B.
Horizontally and in a direction parallel to the wave's direction of motion.
- C.
Horizontally and in a direction perpendicular to the wave's direction of motion.
- D.
None of the given answers
- 11.Electromagnetic waves are
- A.
Longitudinal.
- B.
Transverse.
- C.
Both longitudinal and transverse.
- D.
Neither longitudinal or transverse.
- 12.Of the following, which is not electromagnetic in nature?
- A.
Microwaves
- B.
Gamma rays
- C.
Sound waves
- D.
Radio waves
- 13.Visible light ranges in wavelength from
- A.
400 μm to 750 μm.
- B.
400 nm to 750 nm.
- C.
500 μm to 850 μm.
- D.
500 nm to 850 nm.
- 14.The energy an electromagnetic wave transports per unit time per unit area is the
- A.
Energy density.
- B.
Power.
- C.
Intensity.
- D.
Radiation pressure.
- 15.The force per unit area exerted by an electromagnetic wave is called the
- A.
Energy density.
- B.
Power.
- C.
Intensity.
- D.
Radiation pressure.
- 16.Which of the following correctly lists electromagnetic waves in order from longest to shortest wavelength?
- A.
Gamma rays, ultraviolet, infrared, microwaves
- B.
Microwaves, ultraviolet, visible light, gamma rays
- C.
Radio waves, infrared, gamma rays, ultraviolet
- D.
Television, infrared, visible light, X-rays
- 17.If the electric field in an EM wave has a peak value of 2.0 V/m, what is the peak value of the magnetic field?
- A.
6.7 nT
- B.
2.0 T
- C.
3.0 * 10^8 T
- D.
None of the given answers
- 18.What is the wavelength of light waves if their frequency is 5.0 * 10^14 Hz?
- A.
0.60 m
- B.
6.0 mm
- C.
0.060 mm
- D.
0.60 μm
- 19.What is the wavelength of a 92.9-MHz radio wave?
- A.
32 mm
- B.
32 cm
- C.
3.2 m
- D.
32 m
- 20.What is the wavelength of a radio wave signal transmitted at a frequency of 7.2 MHz?
- A.
42 m
- B.
4.2 m
- C.
29 m
- D.
0.024 m
- 21.What is the wavelength for the carrier wave in the station WBRN 1460?
- A.
2.05 m
- B.
20.5 m
- C.
205 m
- D.
2.05 km
- 22.What is the frequency of 20 mm microwaves?
- A.
100 MHz
- B.
400 MHz
- C.
15 GHz
- D.
73 GHz
- 23.How far does light travel in 1.0 μs?
- A.
3.0 * 10^14 m
- B.
0.30 km
- C.
3.0 m
- D.
30 cm
- 24.How long does it take light to travel 1.0 m?
- A.
3.3 ns
- B.
3.3 μs
- C.
3.3 ms
- D.
3.3 s
- 25.How long does it take the signal from a local radio station to travel 20 miles?
- A.
2.8 s
- B.
108 ms
- C.
38 ms
- D.
108 ms
Questions: 33 | Attempts: 2710 | Last updated: Mar 22, 2022
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Sample QuestionIn an electromagnetic wave
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Sample QuestionWhich of the following types of electromagnetic wave has the longest wavelength: