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how does an electric bell work?

An electric bell is a mechanical bell that functions by means of an electromagnet. When an electric current is applied, it produces a repetitive buzzing or clanging sound.

An electric bell contains an electromagnet, consisting of coils of insulated wire wound round iron rods. When an electric current flows through the coils, the rods become magnetic and attract a piece of iron attached to a clapper. The clapper hits the bell and makes it ring.

1. When the switch is closed (when the bell is turned on) the electromagnet inside the bell turns on which attracts the iron bar.

2. This movement causes a hammer to strike the bell.

3. When the hammer moves, it pulls two contacts away from each other.

4. This breaks the circuit and the electromagnet loses its magnetism, so the hammer and iron bar return to their original position.

5. This causes the contacts to touch again, turning the electromagnet back on attracting the iron bar which causes the hammer to hit the bell. This repeats again and again extremely quickly, causing the ringing or buzzing sound, until the switch is opened (the bell turned off).