Problem 2185. Speed of light:Experiment

Created by Zikobrelli

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in 1849, Fizeau set up an experiment to measure the speed of light. The discription of this experiment can be found on wikipedia. http://commons.wikimedia.org/wiki/File:Zahnradmethode_Fizeau.jpg

A animation can be found on http://fr.wikipedia.org/wiki/Appareil_de_Fizeau

L is the source of light

The cogwheel 'Z' has T number of teeth,rotating at X RPM

d is the distance(in km) separating lenses S1 and S2.

Given T, X and d, what was Fizeau's approximation of the speed of light in km/s?

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Last solution submitted on Aug 29, 2019

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Ben Petschel on 6 Sep 2016

The units are wrong. d is the distance (in metres) from each lens to the cogwheel (not the distance separating). X is in rps not rpm. The required speed of light is in m/s not km/s.

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Problem 2185. Speed of light:Experiment

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Problem 2185. Speed of light:Experiment

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