Microwave everywhere, even if the ban on the microwave oven is useless, as long as the control of the radiation power on the line, computer equipment have similar radiation, cell phone signals will not be very harmful to the human body, and the use of microwave ovens do bring a lot of convenience to life.
Microwave oven (microwave oven/microwave), is a microwave heating food modern cooking stove, invented by the United States Spencer. Microwave is a kind of electromagnetic wave. Microwave oven by the power supply, magnetron, control circuits and cooking cavity and other components.
The power supply to the magnetron provides about 4000 volts of high voltage, the magnetron in the power supply excitation, continuous generation of microwaves, and then through the waveguide system, coupled to the cooking cavity. Near the inlet of the cooking cavity, there is a rotatable stirrer, because the stirrer is a fan-like metal, rotating up to the microwave has all directions of reflection, so the microwave energy can be evenly distributed in the cooking cavity.
The principle of microwave heating is when the microwave radiation to the food, food always contains a certain amount of water, and water is composed of polar molecules, the orientation of such polar molecules will change with the microwave field. The power range of a microwave oven is generally 500 to 1000 watts. Thus heating the food.
Expanded:
This type of electromagnetic wave is not only much more energetic than the usual radio waves. And also very "personality", microwave a touch of metal on the reflection, metal has no way to absorb or conduct it; microwave can pass through the glass, ceramics, plastics and other insulating materials, but will not consume the energy; and contains water in the food, microwave not only through, and the energy will also be absorbed.
Microwaves are radio waves with a wavelength of 0.001 to 1 meter, which corresponds to a frequency of 30,000 MHz to 300 MHz. In order not to interfere with radar and other communication systems, the operating frequency of microwave ovens are mostly selected 915 MHz or 2450 MHz.
Reference:
Baidu Encyclopedia - Microwave Oven