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Microwave Oven

Strangely the microwave oven, or the microwave was not invented as a way of trying to cook food faster. In fact, its history has nothing to do with cooking or the kitchen!

During World War II two scientists invented the magnetron which is a tube that produces microwaves. It was installed in the British radar system to spot Nazi warplanes.

How microwaves started cooking and heating food was discovered completely by accident. The man who made this accidental discovery was Percy LeBaron Spencer.

Spencer found that the chocolate bar in his pocket had melted because of radar waves. Through experiments he found that microwave heating was able to heat up food much faster than a normal oven could.

Because it was so large, and expensive only restaurants, hotels and institutions could afford to use them.

Thirteen years later, in 1967, the first Radarange that could be used in homes was introduced to the market.

At first, these new home microwave ovens were very expensive and not many people could afford them.

By around 1971, more companies started producing microwaves, and the prices reduced allowing more people to enjoy this quick and easy way of cooking and heating food.

Microwaves are short waves (or high frequency radio waves), which are the shorted of radio waves (some radio waves are about 6 feet long).

The properties of microwaves are such that they do not produce atoms that are minus charged; in other words, heating food with microwaves does not make it radioactive.

So microwave ovens produce microwaves electronically and are controlled by electronic controls so that the amount of heat can be changed depending on what is cooking.

There are four main sections of the microwave oven; the control circuit (that controlles the heat, and magnetron, the waveguide, and the cooking chamber.

As explained earlier, the magnetron is the high powered vacuum tube that makes the microwaves, and the waveguide is the material that directs the microwaves to whatever is cooking.

The cooking chamber is interestingly a modification of the Faraday Cage (invented by Michael Faraday).

This chamber keeps the microwaves safely within the oven without letting it escape into the surroundings.

No one can deny that this great machine has made life a lot easier especially on busy days when all we want to do is reheat some leftover food.

Even so, it has certain concerns that we should pay attention to. Since the food is reheated so quickly, it is said that any bacteria in the food may not be killed. This can lead to food poisoning.

Technology has also introduced many safety devices such as the protective interlock that does not allow the microwave to work when the door is open.

The operation and manufacturing of the microwave oven in closely monitored (in America) by the United States Food and Drug Administration Centre and other agencies to ensure that the radiation is not harmful to human health.