Fizeau, 1851, drag coefficinet

[callejon]

Has Fizeau changed the direction of the water in his experiment?

If no, wenn we change the direction of the water, is it true that we get twice as much change in fringes?

I mean, when we compare the fringes when there are 2 directions of water, is the change more than when we compare one dircetion and no movement of water?

Because I've never read that the direction of water was changed and my teacher says now that it was changed.

 

[pervect]

I haven't been able to find much in the way of reliable information on Fizeau's experiment. Google finds a bunch of crank webpages full of misinformation and little else. The sci.physics.faq on the experimental basis of relativity has only this to say:

http://math.ucr.edu/home/baez/physics/Relativity/SR/experiments.html#2. early experiments

Fizeau -- Measured the speed of light in moving materials. The Fresnel drag coefficient is solidly established by experiments, and is consistent with SR to within experimental resolutions.

 

[cesiumfrog]

is it true that we get twice as much change in fringes [..] when we compare the fringes [between] 2 directions of water[ versus] one dircetion and no movement of water?

Yes, that is the correct understanding but I don't know whether any particular person has bothered to perform that specific check (since there is no obvious reason to doubt it). On the other hand, why don't you just look up Fizeau's original results (using babelfish if necessary); wouldn't it be surprising if someone went to all the effort of preparing an appropriate apparatus and then only used it for flows in one direction?