Question

Galileo tried to use the method, above, to measure the speed of light./ He used clocks that were able to measure times accurately to about 1 second, but failed to measure the speed of light. Note he was sending signals about 1km one way. Describe why he was unable to measure the speed of light. You are encouraged to use calculations to justify your answer.

Answer 1

We know that light travels at \(3\times10^8~m/s\). So at 1 km, light would have been traveling for \(\Large {1000~m\over3\times10^8 m/s}\) or about 3.3 \(\mu s\). Which is 1 millionth the precision that poor old Galileo's instruments could have detected.