How do microwaves cook food?

Microwaves cook food by producing electromagnetic waves that excite water molecules, generating heat which cooks the food from the inside out.

Microwaves are a type of electromagnetic wave, similar to radio waves or light waves, but with a shorter wavelength. These waves are produced by a device inside the microwave oven called a magnetron. When you start the microwave, the magnetron begins to produce microwaves which are then directed into the cooking compartment.

The microwaves penetrate the food and their energy is absorbed by water molecules in the food. This energy causes the water molecules to vibrate rapidly, which generates heat. This heat then cooks the food. This is why foods with a high water content, like vegetables, cook more quickly in a microwave than drier foods.

Unlike conventional ovens, which heat food from the outside in, microwaves cook food from the inside out. This is because the microwaves can penetrate into the food, rather than just heating the surface. This can result in food being cooked more quickly, but it can also lead to uneven cooking if the food is not turned or stirred.

It's also worth noting that microwaves are reflected by metal, which is why you can't use metal containers in a microwave oven. The microwaves would simply bounce off the metal and not cook the food. However, microwaves can pass through glass, plastic, and ceramics, which is why these materials are commonly used for microwave-safe containers.

In summary, microwaves cook food by producing electromagnetic waves that excite water molecules in the food, generating heat. This heat cooks the food from the inside out, which can be quicker but also potentially uneven compared to conventional cooking methods.