Electricity from Magnetism

Faraday discovered that…

a magnetic field could make an electric current

electromagnetic induction

the process of creating a current in a circuit by changing a magnetic field

An electric current is made when…

a magnet moves in a coil of wire or when a wire moves between the poles of a magnet

An electric current is induced because…

a magnetic force can cause electric charges to move

Electric generator

uses electromagnetic induction to change mechanical energy into electrical energy

Alternating current

the electric current produced in the above example changes direction each time the coil makes a half turn

Because the electric current changes direction…

it is an alternating current

Generating electrical energy

falling water, nuclear power plants, burning, winds

falling water

turns a turbine that spins a magnet to produce an electric current

nuclear power plants

use thermal energy to boil water and use the steam to turn a turbine

burning

of coal or gas to make steam

wind

to turn a turbine

transformer

a device that increases or decreases the voltage of alternating current

what is a transformer made up of

two coils of wire wrapped around an iron ring

The _______ coil gets the alternating current from electrical energy source.(The Ring becomes an electromagnet)

primary

step-up

increase the voltage and decreases current

step-down

decreases the voltage and increases current