Microwaves are small (compared to radio waves, which have wavelengths of many centimeters) and can be used to heat or melt a wide range of materials. In astronomy, microwaves are used in radio telescopes to receive signals from planets, stars and galaxies.
A microwave oven uses a magnetron to generate microwaves at high frequencies (in the millimeter wave range). The microwaves bounce back and forth around a food compartment that sits on a revolving glass turntable. The magnetron blasts these microwaves onto the water molecules in the food, which then excite them to vibrate rapidly and produce heat.
The microwaves are directed to the food by a metal waveguide that directs the waves into a cooking chamber where they’re kept from escaping. This is called a Faraday cage, and it’s also an important part of protecting the people inside the kitchen from harmful microwave energy.
When you cook in a microwave, the heat penetrates all the way into the food, despite its being thin. However, for thicker foods, you still need conduction (the transfer of heat from one area to another) and convection (the natural circulation of heat through a liquid) before the food is cooked.
How it works
A microwave uses an electric circuit with a cathode block and an anode block that both have lots of cavities (which are conductive) where the electrons pass through at very high speeds. When this oscillating current interacts with the electrons, it causes them to generate microwaves in the cavities.
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Farberware 1.1 Cu. Ft. Countertop Microwave Oven – 1000 Watts Power, Auto Cook Settings, Defrost, Easy Clean and Child Safety Lock - Stainless
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GE Countertop Microwave Oven, 1,150-watt Capacity, 1.6 Cubic Ft., 8 Auto Setting Cooking Settings, Child-Lock Technology, Kitchen Essentials for the Countertop, Dorm Room or Apartment, Stainless Steel
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COMFEE' EM720CPL-PMB Countertop Microwave Oven with Sound On/Off, ECO Mode and Easy One-Touch Buttons, 0.7cu.ft, 700W, Black
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GE Countertop Microwave Oven, Compact 0.9 Cubic Ft., 900-watt Capacity, 7 Auto Cooking Settings, Child-Lock Technology, Kitchen Essentials for the Countertop, Dorm Room or Apartment, Stainless Steel
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FRIGIDAIRE EMW788RETRO 0.7 cu. ft. Retro Microwave, Black-Gold
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Breville BMO650SIL Compact Wave Soft Close Countertop Microwave Oven, Silver
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BLACK+DECKER Countertop Microwave Oven 0.9 Cu Ft, 6 Auto Menus, Child Lock, Memory Function, 10 Power Levels, Easy One-Touch Start, Digital Panel, 900W
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GE Countertop Microwave Oven,1, 200-watt Capacity, 2.0 Cubic Ft., 8 Auto Setting Cooking Settings, Child-Lock Technology, Kitchen Essentials for the Countertop, Dorm Room or Apartment, Stainless Steel
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