Microwave (or microwave radiation) is a form of electromagnetic energy that has shorter wavelengths than radio waves but longer than infrared waves. It’s part of the electromagnetic spectrum that includes radio waves, infrared, visible light, and ultraviolet radiation.
Modern microwave ovens are a convenience that has lifted household cooking to a new level. They cook food much faster than conventional ovens, saving energy, and they can heat up a joint of meat six times as fast as a traditional oven. The secret to their speed is in the technology they use.
The heart of the device is a magnetron, which generates microwaves by electromagnetism. The magnetron sits within a cylindrical container called the waveguide or cover. The waveguide helps direct microwaves into the cooking cavity, so they can reach the food quickly.
Once in the cooking cavity, microwave rays hit water, sugar, and fat content molecules and start them vibrating, creating heat that turns the food inside-out. This is why only the food in the microwave gets hot; it’s not the air around it.
The turntable, the round plate in the bottom of a microwave, rotates to ensure that the food is heated evenly. It’s important that the plate is placed correctly. If it isn’t, uneven heating occurs and the food won’t cook properly.