Cognitive dissonance

[michael.suede]

hahahah


The speed of gravity

[fzzzy]

Speaking of breaking the speed of light, this reminds me of something I read the other day:

http://en.wikipedia.org/wiki/Charles_Wh ... lectricity

He achieved renown by a great experiment — the measurement of the velocity of electricity in a wire. He cut the wire at the middle, to form a gap which a spark might leap across, and connected its ends to the poles of a Leyden jar filled with electricity. Three sparks were thus produced, one at either end of the wire, and another at the middle. He mounted a tiny mirror on the works of a watch, so that it revolved at a high velocity, and observed the reflections of his three sparks in it. The points of the wire were so arranged that if the sparks were instantaneous, their reflections would appear in one straight line; but the middle one was seen to lag behind the others, because it was an instant later. The electricity had taken a certain time to travel from the ends of the wire to the middle. This time was found by measuring the amount of lag, and comparing it with the known velocity of the mirror. Having got the time, he had only to compare that with the length of half the wire, and he could find the velocity of electricity. However experimental or calculation error led him to conclude that this velocity was 288,000 miles per second, an impossible value as it is faster than the speed of light.

I have to wonder... did the person who wrote that sentence even consider replicating his experiment? This has got to be one of the simplest experiments I can imagine... and today we don't even have to mount a tiny mirror on a watch, we can just film it with a super slow mo digital camera.

"Oh, no, we won't bother replicating his experiment, because we have this equation right here that says he can't possibly be right..."

I really dig the graphic. Thanks