Which statement best explains how iron can become a magnet?
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Question 2
2.
Two parallel copper wires are each carrying the same electrical current in the same direction. Which statement explains how they respond to each other?
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Question 3
3.
Which of the following electromagnets would have the greatest magnetic fi eld?
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Question 4
4.
The diagram below shows a bar magnet within a coil of conducting wire. The magnet is moved back and forth. The magnet never has contact with the wire.
As the magnet is moved, the wire will
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Question 5
5.
The diagram below shows current flow through a wire.
Which of the following represents the magnetic field resulting from the current?
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Question 6
6.
Windmills are used to convert wind energy into a more useful form. In most cases, there are three steps in this process. The energy is in a different form at each step. Which of the following flowcharts shows the most likely order of the energy changes?
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Question 7
7.
In the accompanying diagram, a potential difference is induced in a rectangular wire loop as it is rotated at constant speed between two magnetic poles.
If the direction of the field is reversed and the speed of rotation is doubled, the magnitude of the maximum induced voltage will be
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Question 8
8.
What is the main advantage of using alternating current (AC) over direct current (DC) when transmitting electricity?
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Question 9
9.
The primary coil of a transformer has 400 turns; the secondary coil has 1,000 turns. An alternating current is sent through the primary coil. The voltage in the primary coil has an amplitude of 17 V. Which statement best describes the voltage amplitude in the secondary coil?
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Question 10
10.
The diagram shows a wire loop rotating between magnetic poles. During 360 degrees of rotation from the position shown, the induced voltage changes in