Methods to measure the speed of the light

[honolulu_boy]

Hello,

I would like to know what are the differents methods to measure the speed of the light.

Thanks

 

[zhermes]

Try this http://en.wikipedia.org/wiki/Speed_of_light#Measurement" article

 

[honolulu_boy]

Well I have a problem to understand how Fizeau made his measurements ! What were his tools to measure time ?

 

[zhermes]

Probably crystals, counting the number of vibrations.

 

[honolulu_boy]

Probably crystals, counting the number of vibrations.

How he made the counting ?

 

[zhermes]

Don't know. Some sort of electronics... maybe piezoelectrics.

 

[honolulu_boy]

I don't understand why there is always so few indications on experimental setup in Physic

 

[Geezer]

Well I have a problem to understand how Fizeau made his measurements ! What were his tools to measure time ?

Didn't Fizeau use some spinning wheel with holes in it?

ETA: Here's Fizeau's apparatus: https://secure.wikimedia.org/wikipedia/en/wiki/Fizeau–Foucault_apparatus

 

[Geezer]

I don't understand why there is always so few indications on experimental setup in Physic

The experimental set-ups are generally very well described in the published paper(s) that result from the experiment. This is done so that others can reproduce the experiment, if need be.

 

[zhermes]

Didn't Fizeau use some spinning wheel with holes in it?

Good catch Geezer, my apologies---I was thinking about something entirely different. Fizeau's apparatus doesn't need to measure the time explicitly, it drops out of the equations. My bad.

 

[e.chaniotakis]

For God's sake!
Piezoelectrics in 1800's??
Mirrors and spinning wheels and that's all!

 

[Vanadium 50]

Any reason you felt compelled to mention this after almost 2 years had passed?

 

[e.chaniotakis]

well, if you check my registration date you will see that it is roughly a week. Since then, I have been scrolling down all forums to find topics that interest me the most. Therefore, despite the time that has passed since the last post I wanted to comment.

 

[Drakkith]

well, if you check my registration date you will see that it is roughly a week. Since then, I have been scrolling down all forums to find topics that interest me the most. Therefore, despite the time that has passed since the last post I wanted to comment.

It is generally frowned upon to "resurrect" an old thread. If you have a question about the same topic it is usually better to create a new thread instead, as many of the posters in the original thread may be gone now, and a multi-page thread usually gets far fewer looks than a fresh new one.

PF is not your average forum. We try to maintain high standards in our posts, so bumping an old thread simply because you wanted to comment on it is generally not considered to be a good reason.

 

[e.chaniotakis]

I was not aware of this policy! Thank you for mentioning it to me. From now and on it will be done this way.

 

[Drakkith]

I was not aware of this policy! Thank you for mentioning it to me. From now and on it will be done this way.

No problem, everyone's got to learn somehow!