any ferrous object can
be magnetized or
demagnetized
the space around the magnet is called the
magnet field. a compass placed in the
magnetic field it would align itself along
a line of force going toward the south
magnet
electromagnetics
an electromagnets is insulated wire
wrapped round an iron bar. when a
current pasts through the wire a
magnet field is created
electromagnetics can be use for
scrapyard crane, circuit breaker,
electric bell and a relay
the motor
effect
electric motor can be built using a coil
of wire that is free to rotate between
two opposite magnetic poles. When an
electric current flows through the coil,
the coil experiences a force and moves
the generator
effect and a.c.
genertors
An electric current is produced
when a magnet is moved into a coil
of wire in a circuit. The direction of
the current is reversed when the
magnet is moved out of the coil.
a.c. generator Alternating voltage may be generated by
rotating a coil in the magnetic field or by rotating a
magnetic field
transformer
A transformer changes the potential difference of electricity. It
only works with alternating current