01-11-2018, 03:34 AM
The microwave oven is one of the great inventions of the 20th century -- you can find them in millions of homes and offices around the world. At one time or another, we've all been told not to use metal products, especially aluminum foil, when cooking with a microwave oven. Stories of incredible explosions and fires usually surround these ominous warnings. Why is that? Let's take a look at how microwave ovens work to find out.
As incredible as microwave ovens are, the technology behind them is fairly simple. Microwave ovens use microwaves to heat food. Microwaves are radio waves. In the case of microwave ovens, the commonly used radio wave frequency is roughly 2,500 megahertz (2.5 gigahertz). Radio waves in this frequency range have an interesting property: Water, fats and sugars absorb them. When absorbed they're converted directly into atomic motion -- heat. Microwaves in this frequency range have another interesting property: Most plastics, glass or ceramics don't absorb them. But what about metal?
As incredible as microwave ovens are, the technology behind them is fairly simple. Microwave ovens use microwaves to heat food. Microwaves are radio waves. In the case of microwave ovens, the commonly used radio wave frequency is roughly 2,500 megahertz (2.5 gigahertz). Radio waves in this frequency range have an interesting property: Water, fats and sugars absorb them. When absorbed they're converted directly into atomic motion -- heat. Microwaves in this frequency range have another interesting property: Most plastics, glass or ceramics don't absorb them. But what about metal?