A microwave oven is a cooking appliance that uses food to absorb microwave energy in the microwave field to heat itself. In the microwave oven, the microwave generated by the microwave generator establishes a microwave electric field in the microwave oven cavity, and takes certain measures to make the microwave electric field evenly distributed in the oven cavity as far as possible. Put the food into the microwave electric field, and the control center controls its cooking time and microwave electric field intensity to carry out various cooking processes.
Generally speaking, microwave is a kind of high-frequency electromagnetic wave, which does not produce heat. There are microwaves everywhere in the universe and nature, but there are natural microwaves, which can not heat food because they are scattered and not concentrated. The microwave oven uses its internal magnetron to convert electric energy into microwave and penetrate the food with an oscillation frequency of 2450MHz. When the microwave is absorbed by the food, the polar molecules in the food (such as water, fat, protein, sugar, etc.) are attracted and oscillate rapidly at a speed of 2.45 billion times per second. The macroscopic manifestation of this oscillation is that the food is heated.
The principle of microwave heating is simple: when microwave is radiated to food, food always contains a certain amount of water, and water is composed of polar molecules (the positive and negative charge centers of molecules do not coincide even when the external electric field does not exist). The orientation of this polar molecule will change with the microwave field. Due to this movement of polar molecules in water in food. And the interaction between adjacent molecules, resulting in a phenomenon similar to friction, which increases the water temperature. Therefore, the temperature of food also rises. For food heated by microwave, because its interior is also heated at the same time, the whole object is heated evenly and the heating speed is also fast. At a frequency of 2.45 billion times per second, it goes deep into the food 5cm to heat and accelerate the operation of molecules.
