Electricity & Magnetism
Transcript Electricity & Magnetism
Chapter 3 Section 3
Pages 94 - 101
Objective: Investigate how a magnet can be used to produce
Electricity. Understand how an electric current can produce
a magnetic field.
1. An electric current is induced in a conductor when
The conductor moves through a magnetic field.
2. Electromagnetic Induction: The process of generating an
Electric current from the motion of a conductor through a
3. The flow of an induced current may be constant, or may
D.C. – Direct Current: Current consisting of charges that
Flow in one direction only. (battery)
5. A.C. – Alternating Current: A current consisting of
Charges that move back and forth in a circuit. (home)
6. Electric Generator: A device that transforms mechanical
energy into electrical energy – Opposite of an electric motor.
*A generator uses motion in a magnetic field to produce an
*AC Generator uses slip rings attached to the ends of the
*DC Generator uses a commutator instead of slip rings. A
DC generator is the same as an Electric Motor.
7. The electric company uses giant generators to produce
Electrical energy –instead of a crank and armature it uses
8. Turbine: A large circular device made up of many
9. Transformers: A device that increases or decreases
Voltage. It consists of 2 separate coils of insulated wire
Wrapped around an iron core.
10. Types of Transformers…
*Step-Up Transformer: A transformer that increases
*Step-Down Transformer: A transformer that decreases
10. Transformers are used to transmit electrical energy from
Transformers are also used in fluorescent lights, T.V., Xray
Machines, and doorbells.
11. Renewable Resource: One that can be replaced in nature
At a rate close to the rate at which it is used. (water)
12. Non Renewable Resource: One that exists in a
fixed amount. (coal, oil, natural gas)
13. Ways of Generating Electricity:
Burning Fossil Fuels (COAL, OIL, & Natural Gas)