December 21, 2006 8:55am CST
the telephone enables us to converse with people who are away from us. we can make local calls within the limits of the local phone exchange and trunk calls to far away places. the international trunk telephone system helps us to talk to people who are in other countries, separated from us by the vast oceans. telephones are widely used in offices, business establishments, theatres, hospitals and private residence, day by day, people are becoming more and more conscious of the usefulness of the telephone. in our country the entire telephone network is managed by the government. the telephone was invented by alexander graham bell in the year 1875 when he demostrated the first telephone conversation in march 1876 it must have thrilled his audience. the telephone receiver has two main parts. they are the mouth-piece and the ear-piece. when we talk into the mouthpiece, a diapha\ragm attached to it vibrates according to the variations in the sound. these vibrations produce varying electric current which passes on to the receiver of the party at the other end through the telephone wire. the current thus passes on to the other end causes similar vibrations in the receiver of the party called. these vibrations are converted into sound which can be clearly heard in the receiver. this is how the telephone works..