PHY112 - LESSON 9-13 QUIZZES
EXAM QUESTIONS AND ANSWERS
100% SOLVED
What is the peak electric field strength of an EM wave if the peak magnetic field
strength is 0.1 T? - ANSWER-3 x 107 N/C
Which of the following factors will affect the intensity of an EM wave? - ANSWER-Both
of the above
*figure* A wire loop moves into a magnetic field as shown below. Which of the following
will result? - ANSWER-This will induce a counterclockwise current in the loop.
A particular inductor is connected to a circuit where it experiences a change in current
of 0.8 amps every 0.10 sec. If the inductor has a self-inductance of 2.0 V, what is the
inductance? - ANSWER-0.25 H
A particular electromagnetic wave has a frequency of 5 x 1017 Hz. What is the
wavelength of the wave? - ANSWER-6 x 10-10 m
Which of the following circuit components will function the same regardless of whether
the voltage source is direct or alternating? - ANSWER-Resistors
Which of the following is a true statement? - ANSWER-Electric fields direct away from
positive charges and towards negative charges.
Wave intensity is defined as the - ANSWER-rate of energy delivered to a certain area.
*figure* A wire loop sits motionless in a uniform magnetic field as shown below. Which
of the following changes will induce a clockwise current in the loop? - ANSWER-
Increase the magnetic field strength.
The primary difference between x-ray waves and radio waves is - ANSWER-X-ray
waves are higher frequency.
What is the peak magnetic field strength of an EM wave if the peak electric field
strength is 3500 N/C? - ANSWER-1.2 x 10-5 T
A particular electromagnetic wave has a peak magnetic field strength of 5 x 10-5 T.
What is the average intensity of the electromagnetic wave? - ANSWER-2.99 x 105
W/m2
, Which of the following is a true statement? - ANSWER-Both of the above statements
are true.
(one is movement of charge creates magnetic fields)
The reason why humans cannot see infrared waves is because - ANSWER-the waves
are too long for human eyes to detect.
Which of the following is a true statement? - ANSWER-Electromagnetic waves deliver
an oscillating amount of energy to a given area of space each second.
What is the electric field strength of an EM wave if the peak intensity of the wave is
5000 W/m2? - ANSWER-1372 W/m2
Which of the following statements regarding radio waves and sound waves is accurate?
- ANSWER-None of the above statements are accurate.
*figure* 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? - ANSWER-The loop is not experiencing an induced current, but moving the
loop up or down will induce a current.
Which of the following is a true statement? - ANSWER-Induced emf is proportional to
the rate of change of flux.
Which of the following is a true statement? - ANSWER-Magnetic fields cannot have
monopoles.
At what speed must an object move so that its total energy is 10% greater than its rest
energy? - ANSWER-42% of the speed of light
A wave front can correctly be described as - ANSWER-All of the above statements are
correct.
(one of them is a source of spherical wavelets)
A particular particle has a life expectancy of about 0.15 sec before it will decay. If a
scientist in a lab measures the life span of one of these particles while it is moving at a
speed of 2.5 x 108 m/s, what life span will the scientist observe? - ANSWER-0.27 sec
If an object has a rest energy of approximately 0.51 MeV, the object is most likely -
ANSWER-an electron (m = 9.11 x 10-31 kg).
A person standing still, relative to a fast moving spaceship, measures the tick of the
clock relative to the tick of a clock on the spaceship. When the clock has ticked time t,
the person will observe that the clock on the ship will have ticked a time - ANSWER-less
than t.
EXAM QUESTIONS AND ANSWERS
100% SOLVED
What is the peak electric field strength of an EM wave if the peak magnetic field
strength is 0.1 T? - ANSWER-3 x 107 N/C
Which of the following factors will affect the intensity of an EM wave? - ANSWER-Both
of the above
*figure* A wire loop moves into a magnetic field as shown below. Which of the following
will result? - ANSWER-This will induce a counterclockwise current in the loop.
A particular inductor is connected to a circuit where it experiences a change in current
of 0.8 amps every 0.10 sec. If the inductor has a self-inductance of 2.0 V, what is the
inductance? - ANSWER-0.25 H
A particular electromagnetic wave has a frequency of 5 x 1017 Hz. What is the
wavelength of the wave? - ANSWER-6 x 10-10 m
Which of the following circuit components will function the same regardless of whether
the voltage source is direct or alternating? - ANSWER-Resistors
Which of the following is a true statement? - ANSWER-Electric fields direct away from
positive charges and towards negative charges.
Wave intensity is defined as the - ANSWER-rate of energy delivered to a certain area.
*figure* A wire loop sits motionless in a uniform magnetic field as shown below. Which
of the following changes will induce a clockwise current in the loop? - ANSWER-
Increase the magnetic field strength.
The primary difference between x-ray waves and radio waves is - ANSWER-X-ray
waves are higher frequency.
What is the peak magnetic field strength of an EM wave if the peak electric field
strength is 3500 N/C? - ANSWER-1.2 x 10-5 T
A particular electromagnetic wave has a peak magnetic field strength of 5 x 10-5 T.
What is the average intensity of the electromagnetic wave? - ANSWER-2.99 x 105
W/m2
, Which of the following is a true statement? - ANSWER-Both of the above statements
are true.
(one is movement of charge creates magnetic fields)
The reason why humans cannot see infrared waves is because - ANSWER-the waves
are too long for human eyes to detect.
Which of the following is a true statement? - ANSWER-Electromagnetic waves deliver
an oscillating amount of energy to a given area of space each second.
What is the electric field strength of an EM wave if the peak intensity of the wave is
5000 W/m2? - ANSWER-1372 W/m2
Which of the following statements regarding radio waves and sound waves is accurate?
- ANSWER-None of the above statements are accurate.
*figure* 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? - ANSWER-The loop is not experiencing an induced current, but moving the
loop up or down will induce a current.
Which of the following is a true statement? - ANSWER-Induced emf is proportional to
the rate of change of flux.
Which of the following is a true statement? - ANSWER-Magnetic fields cannot have
monopoles.
At what speed must an object move so that its total energy is 10% greater than its rest
energy? - ANSWER-42% of the speed of light
A wave front can correctly be described as - ANSWER-All of the above statements are
correct.
(one of them is a source of spherical wavelets)
A particular particle has a life expectancy of about 0.15 sec before it will decay. If a
scientist in a lab measures the life span of one of these particles while it is moving at a
speed of 2.5 x 108 m/s, what life span will the scientist observe? - ANSWER-0.27 sec
If an object has a rest energy of approximately 0.51 MeV, the object is most likely -
ANSWER-an electron (m = 9.11 x 10-31 kg).
A person standing still, relative to a fast moving spaceship, measures the tick of the
clock relative to the tick of a clock on the spaceship. When the clock has ticked time t,
the person will observe that the clock on the ship will have ticked a time - ANSWER-less
than t.
