Science & TechFact

You owe the microwave oven to a melted chocolate bar.

In 1945, engineer Percy Spencer at Raytheon was working on magnetrons, the transmitters in radar sets. He noticed a chocolate bar in his pocket had melted. He tried popcorn, then an egg, which exploded. The first oven went on sale in 1947: 1.8 meters tall, 340 kilograms, built for restaurants and ships.

Useful: Microwaves make water molecules vibrate; that's why a dry plate barely warms up.

Source: en.wikipedia.org

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