ELECTROMAGNETS

By wilf And Michael

What electromagnets are used for?

Electric bellsLoud speakersLifting magnetsEnergized door locksRelaysScrap Yards

Electric BellsAn 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.