A microwave oven cooks food by using microwave radiation. The oven contains a microwave generator, usually a magnetron, that produces electromagnetic waves in the microwave frequency range. These waves are then directed into the cooking area of the oven.
When you place food in a microwave oven and start the cooking process, the microwaves emitted by the magnetron penetrate the food and cause water molecules in the food to vibrate rapidly. It is this vibration of water molecules that generates heat and cooks the food.
The microwaves have a specific frequency of around 2.45 gigahertz, which corresponds to the natural resonant frequency of water molecules. This means that the water molecules absorb the microwave energy efficiently, causing them to gain energy and vibrate rapidly. As the water molecules vibrate, they collide with other molecules, transferring heat energy throughout the food.
Unlike traditional ovens that heat food from the outside in, microwaves cook food by generating heat directly within the food. This is why microwaves can cook food quickly and evenly. The penetration depth of the microwaves depends on the frequency and the nature of the food. Foods with higher water content tend to heat up more quickly in a microwave since water molecules absorb the microwaves effectively.
It's worth noting that not all materials are microwave-safe. Metal objects, for example, reflect microwaves and can cause sparks or fires. Additionally, some containers or dishes may not be suitable for use in a microwave oven, as they can become excessively hot or can release harmful chemicals when exposed to microwaves. It's important to follow the manufacturer's instructions and use microwave-safe cookware and containers to ensure safe and effective cooking.