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ELECTROMAGNETS
By wilf And Michael
What electromagnets are used for?
Electric bells
Loud speakers
Lifting magnets
Energized door locks
Relays
Scrap Yards
Electric Bells
An electric bell is worked by an
electromagnet.
When the switch is pushed 'on', current flows
through the coil. The coil becomes an
electromagnet. It attracts the metal strip.
This moves the clanger to hit the bell, but
also breaks the circuit.
The coil is no longer a magnet. The clanger
moves back. The circuit has made a gain.
The bell keeps ringing until the switch is
released.
Loud Speakers
A loudspeaker uses electromagnets. An
electromagnet consists of an iron centre
which has coils of wire tightly wrapped
round it. This is known as a solenoid.
When the current flows through the wires
of the solenoid it produces a magnetic
field round it. the iron core increases the
strength of the magnetic field. A solenoid
can behave like a normal bar magnet,
with a north and south pole. Which is
north and which south depends on the
way the electricity goes through. When
the electricity stops, the magnetism stops
too. Electromagnets are useful because
their magnetism can be turned on and off
by turning the electricity supply on and
off.
Lifting Magnets
These special magnets are
specially made for maximum
lifting power or maximum power
for mounting. The steel cap
focuses the power on the lifting
face of the magnet and the hole
gives you an easy way to attach
these to surfaces. The largest
ones are incredibly powerful.
Energized door locks
An electric door lock assembly
including a solenoid having a plunger
movable between retracted and
extended positions, and a mounting
bracket for mounting the solenoid to
a door or door frame so that the
plunger operatively moves along a
vertical axis between the retracted
and extended positions. A locking arm
or bolt is pivotally connected at a
proximal end there of to the plunger.