Galileo performed an experiment to measure the speed of light by timing how long it took light to travel from a lamp he was holding to an assistant about 1.5 km away. Why was Galileo unable to determine that light had a finite speed?

Light travels very fast

Explanation:

Speed of light is normally estimated as 299704644.54 m/s in air hence radar systems have always been used to measure the distance travelled per unit time. By Galileo experimenting to get the speed of light in the above mentioned set-up, it would be difficult to estimate the speed of light. Therefore, it was obvious that Galileo could not estimate the speed of light. This is because the speed of light is very high. In vacuum, the speed of light is estimated as 299,792,458 m/s and this can't be accurately measured in such mentioned set up by Galileo.