Rio Salado PHY112 Final (Lessons 9-14)
Study Guide with Answers
Question 1
Which of the following is a true statement?
A) Electric fields direct away from both positive and negative charges.
B) Electric fields direct towards both positive and negative charges.
C) Electric fields direct away from positive charges and towards negative charges.
D) Electric fields direct towards positive charges and away from negative charges.
Correct Answer
C) Electric fields direct away from positive charges and towards negative charges.
Question 2
The reason why humans cannot see infrared waves is because
A) the waves are too short for human eyes to detect.
B) the waves are too long for human eyes to detect.
C) the waves are too fast for human eyes to detect.
D) human eyes cannot detect electromagnetic waves.
Correct Answer
B) the waves are too long for human eyes to detect.
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,Question 3
The speed of an electromagnetic wave depends on
A) its frequency of wave oscillations.
B) its wavelength.
C) both of the above.
D) none of the above.
Correct Answer
D) none of the above.
Question 4
Which of the following statements regarding radio waves and sound waves is
accurate?
A. Sound waves are transverse waves.
B. Sound waves and radio waves travel at approximately the same speed.
C. Neither sound waves nor radio waves can travel through water.
D. None of the above statements are accurate.
Correct Answer
Answer: D. None of the above statements are accurate.
Question 5
A maximum peak in an oscillating magnetic field occurs at some time t. At the same
time t, the electric field will experience:
A. a maximum peak.
B. a minimum peak.
C. a zero strength field.
D. none of the above.
Correct Answer
Answer: C. a zero strength field.
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, Question 6
What is the peak magnetic field strength of an EM wave if the peak electric field
strength is 3500 N/C?
A. 3500 T
B. 1.2×10^−5 T
C. 8.5×10^4 T
D. None of the above
Correct Answer
Bpeak=3500/3*10^8
Answer: B. 1.2×10^−5 T
Question 7
Wave intensity is defined as the:
A. energy a wave delivers to a certain area.
B. rate of energy delivered to a certain area.
C. amplitude of an electromagnetic wave at a certain area.
D. field strength of an electromagnetic wave at a certain area.
Correct Answer
Answer: B. rate of energy delivered to a certain area.
Question 8
Current is moving to the right through the wire shown below. A stationary wire loop is
located at a position below the wire. Which of the following statements is accurate?
A. The loop is experiencing a clockwise-induced current.
B. The loop is experiencing a counterclockwise-induced current.
C. The loop is not experiencing an induced current, but moving the loop up or down
will induce a current.
D. The loop is not experiencing an induced current, but moving the loop left or right
will induce a current.
Correct Answer
Answer: C. The loop is not experiencing an induced current, but moving the loop up
or down will induce a current.
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Study Guide with Answers
Question 1
Which of the following is a true statement?
A) Electric fields direct away from both positive and negative charges.
B) Electric fields direct towards both positive and negative charges.
C) Electric fields direct away from positive charges and towards negative charges.
D) Electric fields direct towards positive charges and away from negative charges.
Correct Answer
C) Electric fields direct away from positive charges and towards negative charges.
Question 2
The reason why humans cannot see infrared waves is because
A) the waves are too short for human eyes to detect.
B) the waves are too long for human eyes to detect.
C) the waves are too fast for human eyes to detect.
D) human eyes cannot detect electromagnetic waves.
Correct Answer
B) the waves are too long for human eyes to detect.
Page 1 of 19
,Question 3
The speed of an electromagnetic wave depends on
A) its frequency of wave oscillations.
B) its wavelength.
C) both of the above.
D) none of the above.
Correct Answer
D) none of the above.
Question 4
Which of the following statements regarding radio waves and sound waves is
accurate?
A. Sound waves are transverse waves.
B. Sound waves and radio waves travel at approximately the same speed.
C. Neither sound waves nor radio waves can travel through water.
D. None of the above statements are accurate.
Correct Answer
Answer: D. None of the above statements are accurate.
Question 5
A maximum peak in an oscillating magnetic field occurs at some time t. At the same
time t, the electric field will experience:
A. a maximum peak.
B. a minimum peak.
C. a zero strength field.
D. none of the above.
Correct Answer
Answer: C. a zero strength field.
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, Question 6
What is the peak magnetic field strength of an EM wave if the peak electric field
strength is 3500 N/C?
A. 3500 T
B. 1.2×10^−5 T
C. 8.5×10^4 T
D. None of the above
Correct Answer
Bpeak=3500/3*10^8
Answer: B. 1.2×10^−5 T
Question 7
Wave intensity is defined as the:
A. energy a wave delivers to a certain area.
B. rate of energy delivered to a certain area.
C. amplitude of an electromagnetic wave at a certain area.
D. field strength of an electromagnetic wave at a certain area.
Correct Answer
Answer: B. rate of energy delivered to a certain area.
Question 8
Current is moving to the right through the wire shown below. A stationary wire loop is
located at a position below the wire. Which of the following statements is accurate?
A. The loop is experiencing a clockwise-induced current.
B. The loop is experiencing a counterclockwise-induced current.
C. The loop is not experiencing an induced current, but moving the loop up or down
will induce a current.
D. The loop is not experiencing an induced current, but moving the loop left or right
will induce a current.
Correct Answer
Answer: C. The loop is not experiencing an induced current, but moving the loop up
or down will induce a current.
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