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Name
Date
Electricity
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
Work and Machines
• Electrical forces act at a distance.
• Electric charges can be created and
destroyed.
• All circuits contain electrical resistance.
• Electricity can flow only through an open
circuit.
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 five devices that use electrical energy. Write the forms of energy into which
electrical energy is converted by each device.
Accept all reasonable responses. Possible answers:
lamp—light energy and thermal energy;
hair dryer—thermal energy and kinetic energy;
toaster—thermal energy;
TV—light and sound;
CD player—sound
Electricity
67
Name
Date
Electricity
Section 1 Electric Charge
Skim Section 1 of your book. Write three questions that come to
mind from reading the headings and the illustration captions.
1. Accept all reasonable responses.
2.
3.
Review
Vocabulary Use your book to define gravity.
gravity
attractive force between two objects that depends on the masses
of the objects and the distances between them
New
Vocabulary Read the definitions below. Write the key term that matches each
static electricity
law of conservation of
charge
electric field
conductor
the buildup of electric charge on an object
charge can be transferred, but not created or destroyed
a region of force around an electric charge within which other
charges are attracted or repelled
a material in which electrons are able to move easily
insulator
a material in which electrons are not able to move easily
charging by contact
the process of transferring charge by touching or rubbing
charging by induction
electroscope
electrons on a neutral object are moved by a charged object
a device that detects electric charge
Academic
Vocabulary Use a dictionary to define the term create.
create
68 Electricity
to bring into existence
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
definition in the left column.
Name
Date
Section 1 Electric Charge
Charges Exert
Forces
I found this information
on page
.
(continued)
Model charges and electric fields of two items that have just been
removed from a clothes dryer.
Accept all reasonable responses.
SE, p. 171
RE, p. 91
Encourage clear and
logical drawing rather
than artistic merit.
Suggest that students
use different colors to
represent positive and
negative charges.
I found this information
on page
.
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
SE, p. 172
RE, p. 92
Conductors and
Insulators
I found this information
on page
.
SE, p. 173
RE, p. 93
Encourage students
to identify objects in
the classroom as
conductors or
insulators.
Compare the force of electricity to the force of gravity. Provide
examples to complete the table. Accept all reasonable answers.
Location of Force
Force
Example
Within an atom
Electricity
The attraction between
the electron and proton
of a hydrogen atom.
Between atoms
Electricity
The attraction between
the hydrogen and
oxygen in water.
Between objects
Gravity
The attraction between
me and my book.
Between objects
Electricity
The attraction between
my feet and the carpet
after I scuff my feet on it.
Classify five conductors and five insulators in the correct space
below.
Conductors
Insulators
Accept all reasonable
responses. Students
should include various
metallic objects.
Accept all reasonable
responses. Students
should include various
paper, wood, plastic, and
glass objects.
Electricity
69
Name
Date
Section 1 Electric Charge
Charging Objects
I found this information
on page
.
SE, pp. 174–175
RE, pp. 93–94
(continued)
Describe the type of charging that occurs in each event.
1. Lightning strikes a lightning rod on a tall building.
Charging by induction; Separated charges within a cloud
rearrange the electrons on nearby Earth.
2. The lightning rod moves excess charges to Earth’s surface.
Charging by contact; The charged lightning rod transfers charge
to Earth, which it is touching.
I found this information
on page
.
SE, pp. 176–177
RE, p. 94
Sequence the events that occur when an electroscope is used to
detect a charge on an object.
1. A negatively 2. Electrons
(or positively)
travel
charged
down
(or up) the
object
rod.
touches the
knob at the
top of
beaker.
3. Both leaves
4. The leaves
gain
negative
(or positive)
charges.
repel each
other and
spread
apart.
C ONNECT I T
Hypothesize what might happen if you use electrical
appliances while standing or sitting in water.
Accept all reasonable responses. Water is a conductor. If you were to drop an electrical
appliance into water when it is plugged in, electric charge would be conducted through
the water. If you were in that water, the charge would then be conducted through you,
causing injury or death.
70 Electricity
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
Electroscopes