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Have you ever wondered why a microwave oven can have a see-through window? “Microwaves” are radiation after all. We all know about tempered glass as commonly used in convention ovens, but microwave ovens also have a perforated metal mesh screen on the inside of the glass. How does this help?
How is this perforated screen on microwave ovens effective against microwave radiation?
Beginning with the basics; microwaves are in fact, radiation. High frequency radio waves to be exact, but radiation all the same. But so is any form of heat, light, sound, etc. They too are radiation. Throwing a baseball is in fact, a form of ‘radiation’ in that the ball is ‘radiating away from’ where it started. In short, any linear path movement is radiation and the trajectories of a baseball or a golf ball etc. are in the strictest sense, radiation.

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