Download Lesson 2 Questions

Name ______________________________
Lesson 2 Summary
Use with pp. 14–19
Lesson 2: How do electric charges move?
Vocabulary
electric current electric charges in motion
resistance a property of a material that does not allow electric current
to flow easily through it
series circuit a circuit in which electric charge can flow only in one path
Electric charges that move or flow form
an electric current. Sometimes the
direction and flow of current is controlled.
The current follows a path. This path is
called an electrical circuit.
A closed circuit is a complete loop, or a
whole circle. It has no breaks. A current
can flow through a closed circuit. An open
circuit has one or more breaks. A current
cannot flow through an open circuit.
Conductors, Resistors, and
Insulators
A conductor is a material that allows
electricity to flow easily. The wires, clips,
and switches in a circuit are conductors.
A resistor is a material that resists the
flow of electric current. Resistance means
that the material does not allow electric
current to flow easily. Resistors change
electrical energy into light, heat, and other
kinds of energy. The wire inside a light bulb
is a resistor.
An insulator is a material that has a lot
of resistance. It has so much resistance
that it stops the electric current. The plastic
covering on a wire is an insulator.
Series Circuit
In a series circuit, electric current can
flow in only one path. If the path has a
break, then the current stops.
Chapter 1, Lesson 2 Summary
Batteries provide energy to some circuits.
The energy makes the electric charges move
through the circuit.
In a series circuit, all of the resistors
share the energy. For example, two light
bulbs in a circuit shine with the same
amount of light. What happens when one
light bulb breaks or burns out? The circuit
is open. The current cannot flow. None of
the bulbs can light.
Today most buildings do not use series
circuits.
Energy Changing Form
Resistors change electrical energy into
other kinds of energy. Resistors can convert
electrical energy into heat, light, or motion.
A filament is a very thin coiled wire
inside a light bulb. The filament is a
resistor. It changes electric current into
heat. The filament gets so hot that it glows
and gives off light.
Producing Heat and Light
Every day, you use devices and
appliances that need electricity. Computers,
televisions, light bulbs, and toasters all use
electricity. Some devices change electrical
energy into light. They also produce some
heat. Other devices convert electricity into
heat. They sometimes produce light as well.
Intervention Study Guide
© Pearson Education, Inc. 4
Charges in Motion
Name ______________________________
Lesson 2 Questions
Use with pp. 14–19
Lesson 2 Questions
1. What is the difference between an open circuit and a closed circuit?
2. What does an insulator do to electric current? Give an example of an
insulator.
3. A
resistor changes electrical energy into other forms of energy. In the
Lesson 2 Summary, find two forms of energy that resistors can give off.
Circle the two forms of energy.
© Pearson Education, Inc. 4
4. What is the resistor inside a light bulb?
Intervention Study Guide
Chapter 1, Lesson 2 Questions