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Microwaves Cook From The Inside
Listen to Karl talk about Microwaves Cook From The Inside
(You will need Real Audio which you can download for free Microwaves are very weird. They will make food hot, but they are not hot themselves! We humans started using fire to heat our food about one million years ago. And for most of that million years, we used variations on that theme - such as baking, boiling, steaming, poaching, roasting, grilling, frying and so on. There was no really new way to cook food until we started using microwaves, about half-a-century ago. Even today, most people don't really understand microwaves. But whatever the reason, most people wrongly believe that microwaves cook the food from the inside first.
The first real "use" of microwaves was in radar units during WW II. Radar gave the British the huge advantage of being able to detect the approaching enemy planes at night, or through thick cloud.
Wartime radar began in 1940, when Sir John Randall and Dr. H. A. Boot invented the magnetron, a device to generate microwaves. The magnetron squirted out the microwaves for only a brief instant, and then stopped transmitting. A different part of the radar unit then listened for the echo bouncing back. There would be an echo only if the transmitted radar beam happened to land on a target. Some of the radar beam energy would be bounced off the target back to the radar unit. If the radar unit had to wait for a long time, the incoming planes were far away - but if there was only a short time before the echo arrived, then the planes were very close. | |
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