Inventions Based on Accidental Discoveries - Microwave Oven (Paperback)

Chapters: Microwave Oven. Source: Wikipedia. Pages: 23. Not illustrated. Free updates online. Purchase includes a free trial membership in the publisher's book club where you can select from more than a million books without charge. Excerpt: A microwave oven, or a microwave, is a kitchen appliance that cooks or heats food by dielectric heating. This is accomplished by using microwave radiation to heat water and other polarized molecules within the food. This excitation is fairly uniform, leading to food being more evenly heated throughout (except in thick objects) than generally occurs in other cooking techniques. Basic microwave ovens heat food quickly and efficiently, but do not brown or bake food in the way conventional ovens do. This makes them unsuitable for cooking certain foods, or to achieve certain culinary effects. Additional kinds of heat sources can be added to microwave packaging, or into combination microwave ovens, to add these additional effects. The use of high-frequency electric fields for heating dielectric materials had been proposed in the 1930s, for example US patent 2,147,689 (application by Bell Telephone Laboratories, dated 1937) states "This invention relates to heating systems for dielectric materials and the object of the invention is to heat such materials uniformly and substantially simultaneously throughout their mass. ... It has been proposed therefore to heat such materials simultaneously throughout their mass by means of the dielectric loss produced in them when they are subjected to a high voltage, high frequency field." The heating effect of microwaves was discovered accidentally in 1945. Percy Spencer, an American self-taught engineer from Howland, Maine, was building magnetrons for radar sets with the American company Raytheon. He was working on an active radar set when he noticed that a peanut chocolate bar he had in his pocket started to melt. The radar had melted his chocolate bar with...More: http: //booksllc.net/?id=5801