A microwave is a common kitchen appliance used for heating and cooking food. The way a microwave heats a meal is through a process called dielectric heating.
Microwaves are a form of electromagnetic radiation, similar to radio waves, but with a higher frequency and shorter wavelength. The microwaves are generated by a magnetron, a device that converts electrical energy into electromagnetic waves.
When you place your meal in the microwave, the microwaves produced by the magnetron penetrate the food and are absorbed by the water, fats, and sugars in the food. These molecules have a positive and negative end and are therefore called polar molecules.
As the microwaves are absorbed, the polar molecules begin to vibrate, and this vibration creates heat. The heat generated from this process is what cooks or reheats your food.
The microwaves penetrate the food to a depth of about 1-2 inches, which is why microwaves can heat food quickly and evenly, even in thicker or denser foods. However, microwaves are not able to penetrate metal, which is why it is not safe to put metal objects in the microwave.
Another advantage of microwave cooking is that it is a dry cooking method, meaning that it doesn’t require the addition of oil or other fats. This makes it a healthier option for cooking certain foods.
In summary, microwaves use dielectric heating to heat food. The microwaves are absorbed by the polar molecules in the food, which creates heat and cooks or reheats the food. While there are some limitations to what can be cooked in a microwave, it is a quick and convenient way to heat up meals.