The microwave was invented by accident after a chocolate bar melted in an engineer's pocket.
Why it is true
In 1945, Percy Spencer, an engineer at Raytheon, was working with a magnetron when he noticed that the chocolate bar in his pocket had melted. Intrigued, he tested the effect with popcorn and an egg, which exploded. Thus the microwave oven was born, patented in 1946.
Source: BBC Future
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