Voltage applied to a conductor creates a magnetic field around that conductor. It is possible to reverse this process and for a magnetic field to generate a voltage in a conductor. For this to occur, there must be some relative motion between the conductor and the magnetic field. Electromagnetic induction takes place whenever a conductor moves through a magnetic field or when a magnetic field moves across a conductor. The voltage inducted in the conductor is called electromotive force. If the conductor is connected in a complete circuit, a current will flow. This module covers the definition of electromagnetic induction, voltage generators, the left hand rule, solenoids, relays, and transformers.
Learning Objectives
At the end of this module, you will be able to:
- Describe how a magnetic field affects a moving conductor in that field
- Describe the relationship between an electric current and a magnetic field
- Explain how a solenoid works
- List some common applications of solenoids
- Describe how a speaker works
- Describe how a generator makes electricity
- Explain the difference between an AC and DC generator
- Describe how a motor works
- Explain how transformers are used in a power system