Mondo Knows Facts
The microwave oven was discovered accidentally by radar engineer Percy Spencer
A melting candy bar near an active radar magnetron tube led to the commercial microwave oven in 1945
In 1945 while testing cavity magnetron tubes for military radar at Raytheon, engineer Percy Spencer noticed that a peanut candy bar in his pocket had melted completely. He realized that high-frequency radio microwaves caused water molecules in food to vibrate and produce thermal energy. Raytheon patented the technology and manufactured the first commercial Radarange microwave oven.
Where this comes from
United States Patent and Trademark Office
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Tags: microwave, appliances, radar
The microwave oven was discovered accidentally by radar engineer Percy Spencer: the short answers
- Where does this come from, and can I check it?
- A melting candy bar near an active radar magnetron tube led to the commercial microwave oven in 1945. The figure is taken from United States Patent and Trademark Office, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.
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