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Question
How does the magnetic effect of electric current help in the working of an electric bell? Explain with the help of a diagram.
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Solution
The door bell or the electric bell makes use of the principle of an electromagnet. A horseshoe type of electromagnet is used in an electric bell which is connected to the source of current through a switch. It has a metallic gong, a hammer to strike the gong and screw attached to a soft iron strip.
When the button is pressed, the circuit is complete and the hammer gets attracted to the gong thereby striking it to produce a ringing sound.
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