Generators

Definition

A generator is a device that converts mechanical energy into electrical energy through electromagnetic induction. It typically consists of a rotating coil within a magnetic field.

5 Must Know Facts For Your Next Test

1. Generators operate based on Faraday's Law of Electromagnetic Induction, which states that an electromotive force (emf) is induced in a conductor when it experiences a changing magnetic field.
2. The output voltage of a generator is directly proportional to the rate of change of the magnetic flux.
3. Generators produce alternating current (AC) due to the rotation of coils within the magnetic field, causing the direction of induced emf to alternate.
4. Back emf, also known as counter emf, is generated within the coil and opposes the applied mechanical energy, impacting the efficiency and load characteristics.
5. The frequency of the alternating current produced by a generator depends on the speed at which its rotor spins.

Review Questions

• What principle does a generator operate on?
• How does back emf affect the operation of a generator?
• Why do generators typically produce alternating current (AC)?

Related terms

Electromagnetic Induction:

The process by which an electromotive force (emf) is generated in a closed circuit by varying its magnetic environment.

Faraday's Law: A fundamental law stating that an electromotive force is induced in proportion to the rate of change of magnetic flux.

Alternating Current (AC):

An electric current that reverses its direction periodically, commonly produced by generators.