## anonymous one year ago How was the speed of light measured in a precise way? A. by timing how long it takes for an assistant far away to turn on a lantern after the scientist turns one on B. by watching for eclipses C. by timing the speed of falling meteorites D. by using rotating mirrors to measure light's round trip travel to a distant mountain :O :/

1. Michele_Laino

please wait a moment, since a student asked me for help

2. anonymous

ok!! :D

3. Michele_Laino

please wait, I'm searching for your answer into my textbook

4. anonymous

ok!!

5. Michele_Laino

here is my answer: In the past 1927, the rotant mirros method has been used by Michelson between Mount Wilson and Mount S. Antonio in California. The distance between those mountains is 35 Km

6. Michele_Laino

rotating mirrors*

7. anonymous

ohh so it should be choice D? what an interesting way to measure light! :O

8. Michele_Laino

yes!

9. Michele_Laino

here is the value of c which Michelson found: $\Large c = \left( {298,000 \pm 500} \right)Km/\sec$

10. anonymous

oh yay!! thank you!! :D and ooh :O

11. Michele_Laino

thank you!! :)