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Measuring the Speed of Light With Valentine's Day Chocolate
Cytotoxic writes "What to do with all of those leftover Valentine's Day chocolates? — a common problem for the Slashdot crowd. The folks over at Wired magazine have an answer for you in a nice article showing how to measure the speed of light with a microwave and some chocolate. A simple yet surprisingly accurate method that can be used to introduce the scientific method to children and others in need of a scientific education."
I think you mean approximately 300 000 km/s, not km/h. You're only out by a factor of 3600, no worries!
Modding "-1, Troll" is not a proper response if you disagree with me. Try reason.
Now this is very informative ;-)
Actually, not that much since you did not specify in which environment it has that "exact speed". Saying the speed of light is 194792442 m/s or any value is just as precise.
Now, saying that c is constant equal to 299792458 m/s is absolutely correct although, the speed of light is actually:
c/n where n is the refraction index.
In a microwave oven at sea level, the speed of light is *approximately* 299792458/1.0003 = 299702547 m/s
Everything I write is lies, read between the lines.
Aslo, the article is wrong:
The demonstration works because microwave ovens produce standing waves -- waves that move "up" and "down" in place, instead of rolling forward like waves in the ocean.
Ocean waves don't "move forward".
While the individual particles do not, the wave itself does.
He is mistaken on the meaning of a standing wave. It is not the same as a transverse wave (which seems to be why he is comparing them to a longitudinal wave).
The oven is designed to be just the right size to cause the microwaves to reflect off the walls so that the peaks and valleys line up perfectly, creating "hot spots" (actually, lines of heat).
Disproved by direct observation. Go into any store and you'll see microwaves in various sizes. The perfect microwave doesn't have "hot spots".
Again, he's wrong about it being 'designed' for the purpose of having hot spots, but the design does result in hot spots. These occur regardless of oven size, they will simply be located in different locations. This is caused by reflections off internal surfaces acting like two signal sources.
While it may be conceivable to create a 'perfect' microwave with no standing wave nodes, it would be pointless. Besides, he wasn't using an 'ideal' microwave, just a regular off-the-shelf microwave, which does have standing waves.
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