Electromagnets!Electromagnets! By Jack and Bella

These are products where electric magnets are used in them!

Electric bells like the ones used in most schools also contain an electromagnet. When the current flows through the circuit, the electromagnet makes a magnetic field. The electromagnet attracts the springy metal arm. The arm hits the gong, which makes a sound. The circuit is broken now the arm is out of position. The electromagnet is turned off and the springy metal arm moves back. The circuit is complete again. The cycle repeats as long as the switch is closed. Check your understanding of this with the animation. Electric bells like the ones used in most schools also contain an electromagnet. When the current flows through the circuit, the electromagnet makes a magnetic field. The electromagnet attracts the springy metal arm. The arm hits the gong, which makes a sound. The circuit is broken now the arm is out of position. The electromagnet is turned off and the springy metal arm moves back. The circuit is complete again. The cycle repeats as long as the switch is closed. Check your understanding of this with the animation. Electric bells!

Loud speakers! The movement of the coil causes a cone, which is attached to the coil, to move back and forth. This compresses and decompresses the air thereby generating sound waves. The loudspeaker is a TRANSDUCER converting one form of energy to another. The most common type of loudspeaker is the MOVING COIL speaker, where a coil of wire is suspended in the magnetic field of a circular magnet. When a speech current is passed through the coil a varying magnetic field is generated by the coil. The two magnetic fields interact causing movement of the coil.

Lifting magnets! All industrial lifting magnets are electromagnets. From the outside, you see only a heavy cast or machined steel casing and a cover plate. Inside is a winding aluminium or copper electrical conductor. Each layer of the coil is separated by a thin layer of insulation. The inside of the casing is also coated with insulation. The cover plate is a sheet of manganese, providing an extremely hard, non-magnetic protective shield for the coils. The final component is a cable carrying 230 volts of DC current.

Energized door locks! An electric door lock includes a handle rotatable attached to a housing, a lock device engaged in the housing, a follower rotatable secure the handle to the housing, an electromagnetic control device having a receptacle rotatable received in the follower, a plunger slidably engaged in the receptacle and extendible out of the receptacle to engage with the follower, and a latching device for selectively latching the plunger to the receptacle. The plunger may be selectively actuated to engage with the follower either by the lock device and correct keys or by the electromagnetic control device with correctly entered passwords or secret codes.

All relays contain a sensing unit, the electric coil, which is powered by AC or DC current. When the applied current or voltage exceeds a threshold value, the coil activates the armature, which operates either to close the open contacts or to open the closed contacts. When a power is supplied to the coil, it generates a magnetic force that actuates the switch mechanism. The magnetic force is, in effect, relaying the action from one circuit to another. The first circuit is called the control circuit; the second is called the load circuit. Relays!