# Study Guide 3-1

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Using Electricity and Magnetism
Study Guide Section 3 - 1
_ Study Guide 3 - 1______________
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1. Circle the letter of each sentence that is true about electric current and magnetism.
a. A wire with a current has a magnetic field.
b. You can see electromagnetism around a wire.
c. Iron filings can map out a magnetic field around a wire with a current.
d. A wire with no current has a magnetic field.
2. What are the three characteristics of a magnetic field produced by a current?
a. ____________________________________________________________________________________
b. ____________________________________________________________________________________
c. ____________________________________________________________________________________
3. Circle each of the sentences that is true about solenoids.
a. The strength of the magnetic field increases as the number of loops increases.
b. The north and south poles of a solenoid change with the direction of the current.
c. By winding a wire with a current into many loops, you weaken the magnetic field in the center
of the coil.
d. If wire with a current is twisted into a loop, the magnetic field lines become bunched up inside
the loop.
4. Describe four ways you can increase the strength of an electromagnet.
a. ____________________________________________________________________________________
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b. ____________________________________________________________________________________
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c. ____________________________________________________________________________________
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d. ____________________________________________________________________________________
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5.
____________________________________ - a solenoid with a ferromagnetic core
6. _____________________________________ - the relationship between electricity and magnetism
7. _____________________________________ - a coil of wire with a current
&copy; Pearson Education, Inc., publishing as Pearson Prentice Hall. Winds: Section 3-1 – Using Electricity and Magnetism
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