Question

Draw a neat and labelled diagram of an electric bell and describe its working.

Answer 1

Working of an electric bell:

• When the switch is pushed on, the circuit gets completed and current starts flowing through the U-shaped electromagnet which creates a magnetic field in the core. This attracts the iron armature.
• Now, when the armature moves towards the electromagnet, the hammer strikes the gong and the bell rings. But as the armature moves towards the electromagnet, the contact with the adjustment screw breaks which breaks the closed circuit and stops the current.
• When there is no current in the coil of the electromagnet, the electromagnet does not behave like a magnet. The armature returns to its original position. This making and breaking of the circuit of the electromagnet continue as long as the button remains pressed.