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CBSE Class 9 Answered

Working of telephone
Asked by | 24 Jun, 2008, 07:54: PM
answered-by-expert Expert Answer

The telephone operates on simple principles. A telephone mouthpiece contains a thin metallic coating separated from an electrode by a thin barrier (today we use plastic) which connects to a wire carrying an electric current. When a person speaks into the mouthpiece, the acoustic vibrations from her speech push the metallic coating slightly closer to the electrode, resulting in variations in voltage and therefore a speedy conversion from acoustic to electric energy. The electric pulses are conveyed through a wire to the speaker on the other end, where electric pulses are converted into acoustic energy again.

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toppers expert

Answered by | 29 Jun, 2008, 11:32: PM

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