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Date: | Wed, 26 Oct 2005 08:38:15 -0700 |
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Hello clever and creative folks.
Have any of you ever tried to "measure" the speed of light with a microwave? The idea goes like this: you put a layer of melty food (chocolate chips or processed cheese slices) in the microwave on a plate or tray, which you cleverly position so that the turntable doesn't turn it around. You zap it for about 20 seconds, or until isolated spots start to melt. The melted bits represent antinodes of the standing waves in the oven. So, the distance between melted bits should be half the wavelength of the microwaves. The frequency of the microwaves is printed on the oven itself, usually 2450 MHz. wavelength x frequency = c.
Now, I've tried this with many different foodstuffs, at the bottom and the middle of the several ovens, with and without a cup of water to absorb microwaves, on low and high powers, and the closest I get to the real value of c is still 25% off. In fact, I'm quite consistently 25% high. And yes, I have double and triple checked the frequency.
I'd love to hear from anyone else who's tried this... or who would like to try it and tell me what happens! If nothing else, you'll end up with a lot of half-melted chocolate chips to share with your colleagues.
thanks,
sandy
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