Download Chapter 7 Sec 1

Name
Date
Magnetism and Its Uses
Before You Read
Before you read the chapter, respond to these statements.
1. Write an A if you agree with the statement.
2. Write a D if you disagree with the statement.
Before You
Read
Magnetism
• A magnetic field is weakest close to the
magnet.
• The north pole of a compass always points
to Earth’s south magnetic pole.
• Moving charges can create magnetic fields.
• Windmills change chemical energy into
electrical energy.
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
Construct the Foldable as directed at the beginning of this chapter.
Science Journal
List three things you know about magnets.
Student responses will vary, but may include magnets attract some metals, likes
repel, and opposites attract.
Magnetism and Its Uses
79
Name
Date
Magnetism and Its Uses
Section 1 Magnetism
Skim through Section 1 of your book. Read the headings and the
illustration captions.Write three questions that come to mind.
1. Accept all reasonable responses.
2.
3.
Review
Vocabulary Define electric field to show its scientific meaning.
electric field
surrounds an electric charge and exerts a force on other electric
charges
New
Vocabulary Read the definitions below, then write the key term for each one
magnetism
properties and interactions of magnets
magnetic field
something that exerts a force on magnets and objects made of
magnetic materials
magnetic pole
a region where a magnet’s force is strongest
magnetic domain
a group of atoms with aligned magnetic poles
Academic
Vocabulary Define region as it might be used to describe magnets.
region
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Magnetism and Its Uses
an area of activity; an area in which a magnet has influence
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
in the left column.
Name
Date
Section 1 Magnetism
Magnets,
Magnetic Fields
I found this information
on page
.
SE, pp. 202–205
RE, pp. 108–110
Have students work
with a partner to find
the important points
about magnets.
(continued)
Organize important facts about magnets by completing the
outline. Accept all reasonable responses.
Magnets
A. Magnetic force
1. Magnets apply attractive or repulsive force.
2. Interaction of two magnets depends on orientation.
3. Force between two magnets increases as they move
closer together.
B. Magnetic field
1. a force exerted on other magnets and objects made of
magnetic material
2. strongest close to the magnet
3. represented by lines with arrows to show direction
C. Magnetic poles
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
1. All magnets have a north and south pole.
2. Magnetic field is strongest at the poles.
3. Magnetic field lines go from north pole to south
pole.
4. Interaction of two magnets
a. Like magnetic poles repel each other.
b. Unlike magnetic poles attract each other.
D. Compass
1. needle is a small bar magnet
2. turns to line up with Earth’s magnetic field
3. points north toward Earth’s south magnetic pole
E. Earth as a magnet
1. South magnetic pole is near geographic north pole.
2. North magnetic pole is near geographic south pole.
3. Cause is unknown—perhaps related to inner core of
iron and nickel.
Magnetism and Its Uses
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(continued)
Magnetic
Materials
Classify each metal as magnetic or nonmagnetic.
aluminum
iron
I found this information
on page
.
SE, p. 207
RE, p. 111
copper
nickel
Magnetic
SE, p. 206
RE, p. 110
I found this information
on page
.
cobalt
mercury
gold
silver
Nonmagnetic
cobalt
iron
nickel
aluminum
copper
mercury
gold
silver
Model a close-up of the magnetic domains of the cross sections
of an iron rod in each of these situations.
Accept all reasonable responses.
S
N
S
N
S
N
N
N
N
S
S
N
S
S
N
S
S
N
N
S
S
N
N
S
N
S
S
N
S
N
N
S
N
N
S
S
N
S
N
N
S
S
S
S
N
S
S
N
N
S
N
S
N
N
normal state
I found this information
on page
.
SE, p. 208
RE, p. 111
rod is brought
rod is heated
near magnet
or dropped
Identify the poles of a magnet before and after it is sliced into
three pieces.
S
N
S
N
S
N
S
N
CONNECT IT
Outline the steps a recycling company might use to separate
metallic, nonmetallic, and other recyclable materials. (Hint: Some of the materials are
magnetic.)
Accept all reasonable responses. Use a large magnet to remove all the magnetic
materials, which are some of the metals. These can be separated further. Hand-sort or
machine-sort the remaining materials, which include recyclable aluminum.
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Magnetism and Its Uses
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
Section 1 Magnetism