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3D Models of Microwaves Appliances for the Kitchen.
A microwave is an appliance intended to heat and cook food by heating the water they contain or the liquids that are added. It works by generating high-frequency radio waves. Water, fats and other substances in food absorb the energy produced by microwaves in a process called dielectric heating (also known as electronic heating, RF heating, high-frequency heating or diathermy). There are molecules whose structure forms electric dipoles, like that of water, which means that they have a partial positive charge at one end and a partial negative charge at the other, and therefore they oscillate in their attempt to align with the alternating electric field of the microwaves. When rotating, friction and shocks occur, which are what raise the temperature. Microwave ovens work in the following way: a device called magnetron converts electrical energy into microwave energy, which in this way reaches the food. Electromagnetic waves stir bipolar molecules present in food, especially water, and this is what raises the temperature. This agitation is a physical mechanism, simple movement of the molecules at the rate of frequency, and does not cause any type of alteration in the chemical composition (except those that are produced by the increase in temperature).
Microwave heating is more efficient in liquid water than in frozen water since, in the solid state of water, the movement of molecules is more limited.
Due to the lower specific heat capacity of fats and oils, and their higher vaporization temperature, they often reach much higher temperatures within microwave ovens. This can cause oil or very fatty foods, such as bacon, temperatures well above the boiling point of water, roasting similar to roasting on the conventional grill or fryers.
Microwave heating can cause excess heating in some materials with low thermal conductivity, which also have dielectric constants that increase with temperature. An example of this is glass, which can show thermal runaway in a microwave oven to the point of fusion. In addition, microwaves can melt some types of rocks, producing small amounts of synthetic lava. Some ceramics can also melt, and can even get their color to clear when cooled. Thermal runaway is more typical of electrically conductive liquids, such as salt water.