25.2. Using Electromagnetism http://www.ck12.org
FIGURE 25.8
In this simple diagram of an electric motor,
the electromagnet is represented by a
rectangular wire. It actually consists of an
iron bar surrounded by a wire coil.energy to kinetic energy.Lesson Review Questions
Recall
- What is a solenoid?
- What determines the strength of a solenoid’s magnetic field?
- Describe how a doorbell uses an electromagnet.
Apply Concepts
- Draw a labeled sketch of an electric motor to show how it uses electromagnetism to convert electrical energy
to kinetic energy.
Think Critically
- Assume that an electromagnet and a solenoid have the same number of turns in their wire coil and the same
amount of current flowing through the wire. Which device has the stronger magnetic field? Explain your
answer.
Points to Consider
In this lesson, you saw how electric current can be used to create a strong electromagnetic field. In the next lesson,
"Generating and Using Electricity," you’ll find out how a magnetic field can be used to generate an electric current.