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Chapter 18
Electromagnetism
A magnet is an object that radiates a force field that is called a magnetic field. (p.512)
Magnetic field
lines
Magnetism is a naturally occurring force that can be felt but not seen.
The compass needles
follow the magnetic field
lines!
Magnets have two poles:
 North Pole – the part of a magnet pointing towards the earth’s north magnetic pole.
 South Pole – pole opposite the north seeking pole.
Electric
current in
wire
creates
magnetic
field!
Chapter: 18
Electricity is related to magnetism! (p. 518)
 Magnetic fields can produce electric current in conductors.
 Whenever electricity flows, a magnetic field is present.
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An electromagnet is a magnet created by an electric field that can be turned on and off.
(p. 519-520)
electromagnets
An electric motor is a device that uses an electric current to turn an axle. (It converts electrical
energy to mechanical energy) See pg 522
(electric motor)
(electric bell)
Chapter: 18
A generator uses motion to produce an electric current.
ex: hydroelectric plant (water turns turbine that turns a generator)
(p. 527)
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