When was Radar Invented?

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Radar was invented during 1930s. Many countries worked on radar at this time, but the first successful radar was built by Britain in 1935. Radar works by sending out radio signals that bounce off distant objects. The radar set detects the signals that return and produces a picture indicating the position of the objects. British and American scientists worked together to invent methods of using short waves called microwaves.

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Communism

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