Have you ever wondered how a microwave works? Inside their strong metal box, there is a generator called a magnetron which takes electricity from the power outlet and converts it into high-powered, 12cm (4.7 inch) radio waves which get blasted into the food compartment through a channel called a wave guide. Meanwhile, the food sits on a turntable, spinning slowly in order for it to cook evenly. The waves bounce back and forth off the reflective metal walls of the food compartment and penetrate inside the food. As they travel through food, they make the molecules inside vibrate more quickly. Vibrating molecules have more thermal energy so the faster the molecules vibrate, the hotter the food becomes. Furthermore, microwaves essentially pass their energy onto the molecules in the food, rapidly heating it up.

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The design of microwave technology is directly related to engineering. Designers applied scientific knowledge and mathematics to make the microwave efficient at its job and practical.

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