Explain construction and working of an electric bell????

An electric bell is an electrical device with mechanical parts that moves when current is passed through it. The bell functions by means of an electromagnet. It produces repetitive buzzing or clanging sound. 

The hammer is attracted towards the electromagnet whenever the circuit is complete. The circuit breaks whenever the hammer moves towards the electromagnet. When the circuit breaks the electromagnet doesn’t attract the hammer. The hammer comes back to its original position due to spring effect. As the hammer comes back to its original position, it touches the metal connector, the circuit is complete again. This cycle continues till the time the key is kept ON.

Electric bells are used as school bells, doorbells and also at rail road crossings.
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