Answer :
Alexander Graham Bell’s big breakthrough came on 10 March 1876 when he used what he called a ‘liquid transmitter’. This was a vertical metal cone with a piece of parchment stretched like a drum over its narrow end at the base. On the outside of the parchment, Bell had glued a cork with a needle stuck in it, pointing into a tiny cup of diluted sulphuric acid.
When he shouted into the open end of the cone, his voice made the parchment vibrate, so the needle moved slightly in relation to a contact in the cup. The needle was wired to a battery and the movement varied the strength of the current passing between the contacts, thus converting sound waves into an electric signal which travelled along a wire to a receiver. While setting up the experiment, Bell spilt some acid on his trousers. Shouting to his assistant, Thomas Watson heard the message on the receiver in another room and rushed through to Bell, who had just made the first phone call.
When he shouted into the open end of the cone, his voice made the parchment vibrate, so the needle moved slightly in relation to a contact in the cup. The needle was wired to a battery and the movement varied the strength of the current passing between the contacts, thus converting sound waves into an electric signal which travelled along a wire to a receiver. While setting up the experiment, Bell spilt some acid on his trousers. Shouting to his assistant, Thomas Watson heard the message on the receiver in another room and rushed through to Bell, who had just made the first phone call.
Final answer:
Alexander Graham Bell patented the telephone in 1876 and formed the National Bell Telephone Company. By 1880, telephones were in use in the United States, and by 1900, the number had increased to 1.35 million. Technology was transforming communication and connecting the country.
Explanation:
Alexander Graham Bell patented the telephone in 1876, although he was not the first to invent the concept. He worked with financiers and businessmen to create the National Bell Telephone Company, which later became AT&T. By 1880, fifty thousand telephones were in use in the United States, and by 1900, that number had increased to 1.35 million.
Technology was rapidly bringing the country into closer contact and changing the rural isolation that had defined America. Thus, the first telephone worked by converting sound waves into variations in an electric current, transmitting the current along a wire, and then converting it back into sound waves at the receiving end. This allowed for the transmission of voice from one telephone to another, enabling communication over long distances.