Download Ch 21 Sec 3 Guided Reading

Name__________________________ Date ___________________ Class____________
Using Electricity and Magnetism
■
Guided Reading and Study
Electricity From Magnetism (pp. 736-743)
This section explains how an electric current can be produced in a
conductor. It also describes how generators and transformers work.
Use Target Reading Skills
When you preview, you look ahead at the material to be read.
Preview Figure 13. Then write two questions that you have about
the diagram in the graphic organizer below. As you read, answer
your questions.
Generators
Q. What are the parts of a generator?
A.
Q.
A.
Induction of Electric Current (pp. 736-739)
1. What is the key when using a magnet and a conductor to induce a current
in the conductor?
2. An electric current is induced in a conductor when the conductor moves
through a(n)
3. What is electromagnetic induction?
4. What are two ways to induce a current in a conductor with a magnet?
a.
b.
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Name _________________________ Date ___________________ Class ___________
Using Electricity and Magnetism
■
Guided Reading and Study
Electricity From Magnetism (continued)
5. Is the following sentence true or false? In an induced current, charges
may flow in one direction only, or they may alternate directions.
6. What does the direction of an induced current depend on?
7. Is the following sentence true or false? An induced current may change
direction.
8. Complete the table about induced currents.
Induced Currents
Induced Current
Abbreviation
Description
Example
a.
AC
b.
Circuits in the home
c.
DC
d.
Batteries
Generators (pp. 740-741)
9. A device that transforms mechanical energy into electrical energy is
called a(n)
10. How is an electric motor the opposite of an electric generator?
11. Is the following sentence true or false? Large generators use armatures
similar to those in a motor.
12. The parts of a generator that rotate with the wire loop and make contact
with the brushes are called
© Pearson Education, Inc., publishing as Pearson Prentice Hall. All rights reserved.
Name__________________________ Date __________________ Class ____________
Using Electricity and Magnetism
■
Guided Reading and Study
Transformers (pp. 741-743)
13. A device that increases or decreases voltage is called a(n)
14. In a transformer, what induces a current in the secondary coil?
15. Why won't a transformer work with direct current?
16. If there are more loops in the secondary coil of a transformer than in the
primary coil, will the voltage in the secondary coil be higher or lower
than in the primary coil?
17. Why is a transformer necessary so that electrical energy can be brought into
a home?
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Name _________________________ Date ___________________ Class ___________
Using Electricity and Magnetism
■
Guided Reading and Study
Electricity From Magnetism (continued)
18. Complete the table below about types of transformers.
Types of Transformers
Type of
Transformer
Increases or
Decreases
Voltage?
a.
b.
c.
b.
Setup
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