I'm not sure if I'm just being paranoid or not but I'd like some explanation as to whether my fears are justified or not.

With a normal microwave oven you can usually end the cycle early by opening the door. However there is no apparent delay between the closing of the 'microwave' (buzzing sound, that I assume produces microwaves) and the opening of the door.

This has led me to the conclusion that it's possible for some microwaves to escape if the door is opened while it's running a cycle. Microwaves have a speed so if they're generated, it will take some time to reach the door by which point it could be open, which means it could continue on and hit my body.

Is this in any way possible?

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    $\begingroup$ Why would you care? $\endgroup$ – WillO Jul 18 '15 at 2:27
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    $\begingroup$ This is about the design of microwave ovens, not about physics. $\endgroup$ – ACuriousMind Jul 18 '15 at 10:46
  • $\begingroup$ @ACuriousMind no it's about how fast microwaves travel, what does the design have to do with it? $\endgroup$ – Aequitas Jul 18 '15 at 12:54
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    $\begingroup$ Microwaves are electromagnetic waves, so they travel at the speed of light. $\endgroup$ – march Jul 18 '15 at 13:29
  • $\begingroup$ The microwaves travel at a certain speed, yes. But your question, as currently written (v1), is asking is it is possible that some microwave radiation can escape when you exit early from a cycle. That's not a physics question, but a design question (are they produced this way vs that way). $\endgroup$ – Kyle Kanos Jul 18 '15 at 14:02

This actually happens: the microwaves continue for a moment as the door opens. A recent news item talked about the Parkes radio telescope in New South Wales, Australia having trouble with perytons, which are short microwave bursts of terrestrial origins. The Parkes telescope was having trouble finding the source of this interference, and finally tracked it down to a microwave oven in the facility's kitchen.

When the oven's door was opened before stopping the microwaves, there would be a final burst of energy out the door before the magnetron was shut off. Interesting part: although consumer microwave ovens usually operate at 2.45GHz, the "perytons" were generated at lower frequencies (as low as 1.4GHz), possibly because of the change of resonance as the formerly sealed oven was being opened.

The bursts were only dozens of milliseconds long, though, so it's extremely doubtful that the escaped energy could harm you. (BTW, I actually do this myself all the time, and to quote Steve Martin, it doesn't affect me.)


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