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Background and Identification
The microwave oven, more commonly referred to as the microwave, is an electric oven that uses electromagnetic radiation in the microwave frequency range to heat food. Electromagnetic waves of small wavelengths were able to be produced with the development of the cavity magnetron. The General Electric Company (GE) Research Laboratories produced an early 6 kilo-watt version and gave it to the U.S. government in 1940. Raytheon and other companies were given contracts to mass produce the cavity magnetron. While working at Raytheon as an engineer, Percy Spencer discovered the high power heating effect of a microwave beam, leading him to create the first microwave oven. His invention was aided by the development of radar technology during the war. Then, GE Appliances was credited with creating the first over-the-range microwave in 1978, the SpaceMaker. Most of the GE microwaves have a similar design and aesthetic, but are available at a variety of price ranges.
- do not place any metal or conductive object into the microwave—results in electric current; dielectric breakdown causes dangerous oxides to form which are unhealthy in large quantities
- water and homogeneous liquids can superheat (liquid reaches temperature a little above its boiling point without vapor bubbles inside liquid) when heated in a smooth-surfaced container; the boiling process can start explosively when the liquid is disturbed (i.e. moving it, adding sugar, stirring).
- eggs can explode due to increased pressure from steam
- insulating plastic foams of all types should be avoided because they can explode or melt
- not all plastics are microwave safe
Parts of a microwave oven (Wikipedia):
- a high-voltage power source, commonly a simple transformer or an electronic power converter, which passes energy to the magnetron
- a high-voltage capacitor connected to the magnetron, transformer and via a diode to the chassis
- a cavity magnetron, which converts high-voltage electric energy to microwave radiation
- a magnetron control circuit (usually with a microcontroller)
- a short waveguide (to couple microwave power from the magnetron into the cooking chamber)
- a metal cooking chamber
- a turntable and/or metal wave guide stirring fan.
- a control panel