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Question
Explain the construction and working of an Telephone.
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Solution
In telephones, a changing magnetic effect causes a thin sheet of metal (diaphragm) to vibrate. The diaphragm is made up a metal that can be attracted to magnets.
- The diaphragm is attached to spring that is fixed to the earpiece.
- When a current flows through the wires, the soft – iron bar becomes an electromagnet.
- The diaphragm becomes attracted to the electromagnet.
- As the person on the other end of the line speaks, his voice cause the current in the circuit to change. This causes the diaphragm in the earpiece to vibrate, producing sound.
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