Question 1

A cordless phone operates at 900 MHz.What is the wavelength of the electromagnetic wave used by this phone? (c = 3.0 × 108 m/s)

Accepted Answer

Question 2

The amplitude of the electric field for a certain type of electromagnetic wave is 570 N/C.What is the amplitude of the  B⃗\vec { B }B  field for that wave? (c = 3.00 × 108 m/s)

Accepted Answer

A)  2.91 µT
B)  1.90 µT
C)  1.10 µT
D)  1.41 µT
E)  2.41 µT

Question 3

Unpolarized light of intensity I0 passes through four ideal polarizing sheets.The polarizing angle of each sheet is rotated 30° from the one before it,so that the last sheet is aligned at 90° to the first sheet.What is the intensity of the light emerging from the fourth sheet in terms of I0?

Accepted Answer

Question 4

If unpolarized light of intensity I0 passes through an ideal polarizer,what is the intensity of the emerging light?

Accepted Answer

A)  I0
B)  I0/2
C)  I0/4
D)  I0/  2\sqrt { 2 }2c-2.7,0,-7.17,-2.7,-13.5,-8c-5.8,-5.3,-9.5,-10,-9.5,-14c0,-2,0.3,-3.3,1,-4c1.3,-2.7,23.83,-20.7,67.5,-54c44.2,-33.3,65.8,-50.3,66.5,-51c1.3,-1.3,3,-2,5,-2c4.7,0,8.7,3.3,12,10s173,378,173,378c0.7,0,35.3,-71,104,-213c68.7,-142,137.5,-285,206.5,-429c69,-144,104.5,-217.7,106.5,-221l0 -0c5.3,-9.3,12,-14,20,-14H400000v40H845.2724s-225.272,467,-225.272,467s-235,486,-235,486c-2.7,4.7,-9,7,-19,7c-6,0,-10,-1,-12,-3s-194,-422,-194,-422s-65,47,-65,47zM834 80h400000v40h-400000z'/>​ 
E)  I0/16

Question 5

A radio transmitter is operating at an average power of  4.00 kW4.00 \mathrm {~kW}4.00 kW  and is radiating uniformly in all directions.What is the average intensity of the signal  8.00 km8.00 \mathrm {~km}8.00 km  from the transmitter?

Accepted Answer

A)  4.97 μW/m2
B)  2.49 μW/m2
C)  0.00497 W/m2
D)  0.00249 W/m2

Question 6

An electromagnetic wave travels in a vacuum in the +y direction,as shown in the figure.If the  E⃗\vec { E }E  field at the origin is along the +z direction,what is the direction of the  B⃗\vec { B }B  field?

Accepted Answer

A)  +z
B)  -z
C)  +y
D)  +x
E)  -x

Question 7

What is the frequency of 20-mm microwaves? (c = 3.0 × 108 m/s)

Accepted Answer

A)  100 MHz
B)  400 MHz
C)  15 GHz
D)  73 GHz

Question 8

A certain part of the electromagnetic spectrum ranges from 200 nm to 400 nm.What is the highest frequency associated with this portion of the spectrum? (c = 3.00 × 108 m/s)

Accepted Answer

A)  1.50 × 1014 Hz
B)  7.50 × 1013 Hz
C)  7.50 × 1014 Hz
D)  7.50 × 1015 Hz
E)  1.50 × 1015 Hz

Question 9

The maximum value of the electric field in an electromagnetic wave is 2.0 V/m.What is the maximum value of the  B⃗\vec { B }B  field in that wave? (c = 3.0 × 108 m/s)

Accepted Answer

A)  6.7 pT
B)  6.7 mT
C)  6.7 nT
D)  6.7 μT
E)  6.7 T

Question 10

A ray of light traveling in water hits a glass surface.The index of refraction of the water is 1.33,and that of the glass is 1.50.At what angle with the plane of the surface must the incident ray strike the glass in order that the polarization of the reflected ray is the greatest?

Accepted Answer

A)  36.9°
B)  33.7°
C)  41.6°
D)  48.4°
E)  53.1°

Question 11

An 800-kHz sinusoidal radio signal is detected at a point 2.1 km distant from a transmitter tower.The  E⃗\vec { E }E  field amplitude of the signal at that point is 0.80 V/m.Assume that the signal power is radiated uniformly in all directions and that radio waves incident upon the ground are completely absorbed.What is the intensity of the radio signal at that point? (ε0 = 8.85 × 10-12 C2/N ∙ m2,μ0 = 4π × 10-7 T ∙ m/A,c = 3.0 × 108 m/s)

Accepted Answer

A)  8.5 × 10-4 W/m2
B)  1.2 × 10-3 W/m2
C)  1.7 × 10-3 W/m2
D)  6.0 × 10-4 W/m2
E)  4.2 × 10-4 W/m2

Question 12

Which one of the following lists gives the correct order of the electromagnetic waves from longer wavelength to shorter wavelength?

Accepted Answer

A)  radio waves, infrared, microwaves, ultraviolet, visible, x-rays, gamma rays
B)  radio waves, ultraviolet, x-rays, microwaves, infrared, visible, gamma rays
C)  radio waves, microwaves, visible, x-rays, infrared, ultraviolet, gamma rays
D)  radio waves, microwaves, infrared, visible, ultraviolet, x-rays, gamma rays
E)  radio waves, infrared, x-rays, microwaves, ultraviolet, visible, gamma rays

Question 13

At a certain instant in time,the  E⃗\vec { E }E  field of an electromagnetic wave in a vacuum points in the -z direction,and the  B⃗\vec { B }B  field points in the +y direction.In what direction is this wave traveling?

Accepted Answer

A)  +x direction
B)  -x direction
C)  +y direction
D)  -z direction
E)  +z direction

Question 14

At a particular point and instant,the  E⃗\vec { E }E  field component of an electromagnetic wave is 15.0 μT.What is the magnetic energy density of this wave at that point and instant? (c = 3.00 × 108 m/s,μ0 = 4π × 10-7 T ∙ m/A,ε0 = 8.85 × 10-12 C2/N ∙ m2)

Accepted Answer

A)  2.26 × 10-4 J/m3
B)  8.95 × 10-5 J/m3
C)  1.79 × 10-4 J/m3
D)  4.47 × 10-4 J/m3
E)  9.72 × 10-5 J/m3

Question 15

What is the maximum value of the  B⃗\vec { B }B  field at a distance of 2.5 m from a light bulb that radiates 100 W of single-frequency sinusoidal electromagnetic waves uniformly in all directions? (ε0 = 8.85 × 10-12 C2/N ∙ m2,μ0 = 4π × 10-7 T ∙ m/A,c = 3.0 × 108 m/s)

Accepted Answer

A)  0.10 μT
B)  0.40 μT
C)  0.50 μT
D)  0.60 μT
E)  0.80 μT

Question 16

A sinusoidal electromagnetic wave has a peak electric field of  8.00kV/m8.00 \mathrm { kV } / \mathrm { m }8.00kV/m  What is the intensity of the wave?  (c=3.0×108 m/s,\left( c = 3.0 	imes 10 ^ { 8 } \mathrm {~m} / \mathrm { s } , ight.(c=3.0×108 m/s,   μ0=4π×10−7 T⋅m/A,\mu _ { 0 } = 4 \pi 	imes 10 ^ { - 7 } \mathrm {~T} \cdot \mathrm { m } / \mathrm { A } ,μ0​=4π×10−7 T⋅m/A,   ε0=8.85×10−12C2/N⋅m2) \left. \varepsilon _ { 0 } = 8.85 	imes 10 ^ { - 12 } \mathrm { C } ^ { 2 } / \mathrm { N } \cdot \mathrm { m } ^ { 2 } ight) ε0​=8.85×10−12C2/N⋅m2)

Accepted Answer

A)  170 kW/m2
B)  85 kW/m2
C)  21 kW/m2
D)  11 kW/m2

Question 17

Which one of the following expressions is the correct representation for the speed of light in vacuum?

Accepted Answer

A)    ε0μ0\sqrt { \varepsilon _ { 0 } \mu _ { 0 } }ε0​μ0​c-2.7,0,-7.17,-2.7,-13.5,-8c-5.8,-5.3,-9.5,-10,-9.5,-14c0,-2,0.3,-3.3,1,-4c1.3,-2.7,23.83,-20.7,67.5,-54c44.2,-33.3,65.8,-50.3,66.5,-51c1.3,-1.3,3,-2,5,-2c4.7,0,8.7,3.3,12,10s173,378,173,378c0.7,0,35.3,-71,104,-213c68.7,-142,137.5,-285,206.5,-429c69,-144,104.5,-217.7,106.5,-221l0 -0c5.3,-9.3,12,-14,20,-14H400000v40H845.2724s-225.272,467,-225.272,467s-235,486,-235,486c-2.7,4.7,-9,7,-19,7c-6,0,-10,-1,-12,-3s-194,-422,-194,-422s-65,47,-65,47zM834 80h400000v40h-400000z'/>​ 
B)    ε0/μ0\sqrt { \varepsilon 0 / \mu 0 }ε0/μ0c34,79.3,68.167,158.7,102.5,238c34.3,79.3,51.8,119.3,52.5,120c340,-704.7,510.7,-1060.3,512,-1067l0 -0c4.7,-7.3,11,-11,19,-11H40000v40H1012.3s-271.3,567,-271.3,567c-38.7,80.7,-84,175,-136,283c-52,108,-89.167,185.3,-111.5,232c-22.3,46.7,-33.8,70.3,-34.5,71c-4.7,4.7,-12.3,7,-23,7s-12,-1,-12,-1s-109,-253,-109,-253c-72.7,-168,-109.3,-252,-110,-252c-10.7,8,-22,16.7,-34,26c-22,17.3,-33.3,26,-34,26s-26,-26,-26,-26s76,-59,76,-59s76,-60,76,-60zM1001 80h400000v40h-400000z'/>​ 
C)    μ0/ε0\sqrt { \mu _ { 0 } / \varepsilon _ { 0 } }μ0​/ε0​c34,79.3,68.167,158.7,102.5,238c34.3,79.3,51.8,119.3,52.5,120c340,-704.7,510.7,-1060.3,512,-1067l0 -0c4.7,-7.3,11,-11,19,-11H40000v40H1012.3s-271.3,567,-271.3,567c-38.7,80.7,-84,175,-136,283c-52,108,-89.167,185.3,-111.5,232c-22.3,46.7,-33.8,70.3,-34.5,71c-4.7,4.7,-12.3,7,-23,7s-12,-1,-12,-1s-109,-253,-109,-253c-72.7,-168,-109.3,-252,-110,-252c-10.7,8,-22,16.7,-34,26c-22,17.3,-33.3,26,-34,26s-26,-26,-26,-26s76,-59,76,-59s76,-60,76,-60zM1001 80h400000v40h-400000z'/>​ 
D)  1 /  ε0μ0\sqrt { \varepsilon _ { 0 } \mu _ { 0 } }ε0​μ0​c-2.7,0,-7.17,-2.7,-13.5,-8c-5.8,-5.3,-9.5,-10,-9.5,-14c0,-2,0.3,-3.3,1,-4c1.3,-2.7,23.83,-20.7,67.5,-54c44.2,-33.3,65.8,-50.3,66.5,-51c1.3,-1.3,3,-2,5,-2c4.7,0,8.7,3.3,12,10s173,378,173,378c0.7,0,35.3,-71,104,-213c68.7,-142,137.5,-285,206.5,-429c69,-144,104.5,-217.7,106.5,-221l0 -0c5.3,-9.3,12,-14,20,-14H400000v40H845.2724s-225.272,467,-225.272,467s-235,486,-235,486c-2.7,4.7,-9,7,-19,7c-6,0,-10,-1,-12,-3s-194,-422,-194,-422s-65,47,-65,47zM834 80h400000v40h-400000z'/>​ 
E)  1 / ε0μ0

Question 18

How much energy is transported across a 1.00-cm2 area per hour by a sinusoidal electromagnetic wave whose  E⃗\vec { E }E  field has the amplitude of 30.4 V/m? (ε0 = 8.85 × 10-12 C2/N ∙ m2,μ0 = 4π × 10-7 T ∙ m/A,c = 3.0 × 108 m/s)

Accepted Answer

A)  0.44 nJ
B)  0.44 μJ
C)  0.44 mJ
D)  0.44 J

Question 19

An ideal polarizer with its transmission axis rotated 30° to the vertical is placed in a beam of unpolarized light of intensity 10 W/m2.After passing through the polarizer,what is intensity of the beam?

Accepted Answer

A)  2.5 W/m2
B)  5.0 W/m2
C)  8.7 W/m2
D)  7.5 W/m2
E)  10 W/m2

Question 20

The wavelength of an electromagnetic wave is 600 nm.What is its frequency? (c = 3.0 × 108 m/s)

Accepted Answer

A)  200 × 1012 Hz
B)  300 × 1012 Hz
C)  400 × 1012 Hz
D)  500 × 1012 Hz
E)  600 × 1012 Hz

Exam 25: Electromagnetic Waves

A cordless phone operates at 900 MHz.What is the wavelength of the electromagnetic wave used by this phone? (c = 3.0 × 10⁸ m/s)

Correct Answer
verified

Correct Answer
verified

The wavelength of an electromagnetic wave is 600 nm.What is its frequency? (c = 3.0 × 10⁸ m/s)

Correct Answer
verified

A certain part of the electromagnetic spectrum ranges from 200 nm to 400 nm.What is the highest frequency associated with this portion of the spectrum? (c = 3.00 × 10⁸ m/s)

Correct Answer
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If unpolarized light of intensity I₀ passes through an ideal polarizer,what is the intensity of the emerging light?

Correct Answer
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An ideal polarizer with its transmission axis rotated 30° to the vertical is placed in a beam of unpolarized light of intensity 10 W/m².After passing through the polarizer,what is intensity of the beam?

Correct Answer
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The maximum value of the electric field in an electromagnetic wave is 2.0 V/m.What is the maximum value of the $\vec { B }$ field in that wave? (c = 3.0 × 10⁸ m/s)

Correct Answer
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The amplitude of the electric field for a certain type of electromagnetic wave is 570 N/C.What is the amplitude of the $\vec { B }$ field for that wave? (c = 3.00 × 10⁸ m/s)

Correct Answer
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Correct Answer
verified

A radio transmitter is operating at an average power of $4.00 \mathrm {~kW}$ and is radiating uniformly in all directions.What is the average intensity of the signal $8.00 \mathrm {~km}$ from the transmitter?

Correct Answer
verified

Unpolarized light of intensity I₀ passes through four ideal polarizing sheets.The polarizing angle of each sheet is rotated 30° from the one before it,so that the last sheet is aligned at 90° to the first sheet.What is the intensity of the light emerging from the fourth sheet in terms of I₀?

Correct Answer
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Which one of the following lists gives the correct order of the electromagnetic waves from longer wavelength to shorter wavelength?

Correct Answer
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What is the maximum value of the $\vec { B }$ field at a distance of 2.5 m from a light bulb that radiates 100 W of single-frequency sinusoidal electromagnetic waves uniformly in all directions? (ε₀ = 8.85 × 10^-12 C²/N ∙ m²,μ₀ = 4π × 10^-7 T ∙ m/A,c = 3.0 × 10⁸ m/s)

Correct Answer
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What is the frequency of 20-mm microwaves? (c = 3.0 × 10⁸ m/s)

Correct Answer
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Correct Answer
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Which one of the following expressions is the correct representation for the speed of light in vacuum?

Correct Answer
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At a certain instant in time,the $\vec { E }$ field of an electromagnetic wave in a vacuum points in the -z direction,and the $\vec { B }$ field points in the +y direction.In what direction is this wave traveling?

Correct Answer
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At a particular point and instant,the $\vec { E }$ field component of an electromagnetic wave is 15.0 μT.What is the magnetic energy density of this wave at that point and instant? (c = 3.00 × 10⁸ m/s,μ₀ = 4π × 10^-7 T ∙ m/A,ε₀ = 8.85 × 10^-12 C²/N ∙ m²)

Correct Answer
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How much energy is transported across a 1.00-cm² area per hour by a sinusoidal electromagnetic wave whose $\vec { E }$ field has the amplitude of 30.4 V/m? (ε₀ = 8.85 × 10^-12 C²/N ∙ m²,μ₀ = 4π × 10^-7 T ∙ m/A,c = 3.0 × 10⁸ m/s)

Correct Answer
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A ray of light traveling in water hits a glass surface.The index of refraction of the water is 1.33,and that of the glass is 1.50.At what angle with the plane of the surface must the incident ray strike the glass in order that the polarization of the reflected ray is the greatest?

Correct Answer
verified

Exam 25: Electromagnetic Waves

A cordless phone operates at 900 MHz.What is the wavelength of the electromagnetic wave used by this phone? (c = 3.0 × 108 m/s)

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

The wavelength of an electromagnetic wave is 600 nm.What is its frequency? (c = 3.0 × 108 m/s)

Correct AnswerverifiedShow Answer

A certain part of the electromagnetic spectrum ranges from 200 nm to 400 nm.What is the highest frequency associated with this portion of the spectrum? (c = 3.00 × 108 m/s)

Correct AnswerverifiedShow Answer

If unpolarized light of intensity I0 passes through an ideal polarizer,what is the intensity of the emerging light?

Correct AnswerverifiedShow Answer

An ideal polarizer with its transmission axis rotated 30° to the vertical is placed in a beam of unpolarized light of intensity 10 W/m2.After passing through the polarizer,what is intensity of the beam?

Correct AnswerverifiedShow Answer

The maximum value of the electric field in an electromagnetic wave is 2.0 V/m.What is the maximum value of the B⃗\vec { B }B field in that wave? (c = 3.0 × 108 m/s)

Correct AnswerverifiedShow Answer

The amplitude of the electric field for a certain type of electromagnetic wave is 570 N/C.What is the amplitude of the B⃗\vec { B }B field for that wave? (c = 3.00 × 108 m/s)

Correct AnswerverifiedShow Answer

An electromagnetic wave travels in a vacuum in the +y direction,as shown in the figure.If the E⃗\vec { E }E field at the origin is along the +z direction,what is the direction of the B⃗\vec { B }B field?

Correct AnswerverifiedShow Answer

A radio transmitter is operating at an average power of 4.00 kW4.00 \mathrm {~kW}4.00 kW and is radiating uniformly in all directions.What is the average intensity of the signal 8.00 km8.00 \mathrm {~km}8.00 km from the transmitter?

Correct AnswerverifiedShow Answer

Unpolarized light of intensity I0 passes through four ideal polarizing sheets.The polarizing angle of each sheet is rotated 30° from the one before it,so that the last sheet is aligned at 90° to the first sheet.What is the intensity of the light emerging from the fourth sheet in terms of I0?

Correct AnswerverifiedShow Answer

Which one of the following lists gives the correct order of the electromagnetic waves from longer wavelength to shorter wavelength?

Correct AnswerverifiedShow Answer

What is the maximum value of the B⃗\vec { B }B field at a distance of 2.5 m from a light bulb that radiates 100 W of single-frequency sinusoidal electromagnetic waves uniformly in all directions? (ε0 = 8.85 × 10-12 C2/N ∙ m2,μ0 = 4π × 10-7 T ∙ m/A,c = 3.0 × 108 m/s)

Correct AnswerverifiedShow Answer

What is the frequency of 20-mm microwaves? (c = 3.0 × 108 m/s)

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

Which one of the following expressions is the correct representation for the speed of light in vacuum?

Correct AnswerverifiedShow Answer

At a certain instant in time,the E⃗\vec { E }E field of an electromagnetic wave in a vacuum points in the -z direction,and the B⃗\vec { B }B field points in the +y direction.In what direction is this wave traveling?

Correct AnswerverifiedShow Answer

At a particular point and instant,the E⃗\vec { E }E field component of an electromagnetic wave is 15.0 μT.What is the magnetic energy density of this wave at that point and instant? (c = 3.00 × 108 m/s,μ0 = 4π × 10-7 T ∙ m/A,ε0 = 8.85 × 10-12 C2/N ∙ m2)

Correct AnswerverifiedShow Answer

How much energy is transported across a 1.00-cm2 area per hour by a sinusoidal electromagnetic wave whose E⃗\vec { E }E field has the amplitude of 30.4 V/m? (ε0 = 8.85 × 10-12 C2/N ∙ m2,μ0 = 4π × 10-7 T ∙ m/A,c = 3.0 × 108 m/s)

Correct AnswerverifiedShow Answer

A ray of light traveling in water hits a glass surface.The index of refraction of the water is 1.33,and that of the glass is 1.50.At what angle with the plane of the surface must the incident ray strike the glass in order that the polarization of the reflected ray is the greatest?

Correct AnswerverifiedShow Answer

A cordless phone operates at 900 MHz.What is the wavelength of the electromagnetic wave used by this phone? (c = 3.0 × 10⁸ m/s)

Correct Answer
verified

Correct Answer
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The wavelength of an electromagnetic wave is 600 nm.What is its frequency? (c = 3.0 × 10⁸ m/s)

Correct Answer
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A certain part of the electromagnetic spectrum ranges from 200 nm to 400 nm.What is the highest frequency associated with this portion of the spectrum? (c = 3.00 × 10⁸ m/s)

Correct Answer
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If unpolarized light of intensity I₀ passes through an ideal polarizer,what is the intensity of the emerging light?

Correct Answer
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An ideal polarizer with its transmission axis rotated 30° to the vertical is placed in a beam of unpolarized light of intensity 10 W/m².After passing through the polarizer,what is intensity of the beam?

Correct Answer
verified

The maximum value of the electric field in an electromagnetic wave is 2.0 V/m.What is the maximum value of the $\vec { B }$ field in that wave? (c = 3.0 × 10⁸ m/s)

Correct Answer
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The amplitude of the electric field for a certain type of electromagnetic wave is 570 N/C.What is the amplitude of the $\vec { B }$ field for that wave? (c = 3.00 × 10⁸ m/s)

Correct Answer
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Correct Answer
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A radio transmitter is operating at an average power of $4.00 \mathrm {~kW}$ and is radiating uniformly in all directions.What is the average intensity of the signal $8.00 \mathrm {~km}$ from the transmitter?

Correct Answer
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Unpolarized light of intensity I₀ passes through four ideal polarizing sheets.The polarizing angle of each sheet is rotated 30° from the one before it,so that the last sheet is aligned at 90° to the first sheet.What is the intensity of the light emerging from the fourth sheet in terms of I₀?

Correct Answer
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Correct Answer
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What is the maximum value of the $\vec { B }$ field at a distance of 2.5 m from a light bulb that radiates 100 W of single-frequency sinusoidal electromagnetic waves uniformly in all directions? (ε₀ = 8.85 × 10^-12 C²/N ∙ m²,μ₀ = 4π × 10^-7 T ∙ m/A,c = 3.0 × 10⁸ m/s)

Correct Answer
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What is the frequency of 20-mm microwaves? (c = 3.0 × 10⁸ m/s)

Correct Answer
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Correct Answer
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Correct Answer
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At a certain instant in time,the $\vec { E }$ field of an electromagnetic wave in a vacuum points in the -z direction,and the $\vec { B }$ field points in the +y direction.In what direction is this wave traveling?

Correct Answer
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At a particular point and instant,the $\vec { E }$ field component of an electromagnetic wave is 15.0 μT.What is the magnetic energy density of this wave at that point and instant? (c = 3.00 × 10⁸ m/s,μ₀ = 4π × 10^-7 T ∙ m/A,ε₀ = 8.85 × 10^-12 C²/N ∙ m²)

Correct Answer
verified

How much energy is transported across a 1.00-cm² area per hour by a sinusoidal electromagnetic wave whose $\vec { E }$ field has the amplitude of 30.4 V/m? (ε₀ = 8.85 × 10^-12 C²/N ∙ m²,μ₀ = 4π × 10^-7 T ∙ m/A,c = 3.0 × 10⁸ m/s)

Correct Answer
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Correct Answer
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