Who first showed that light does NOT travel at infinite speed?
A) Ole Rømer in 1675
B) Thomas Young in 1801
C) James Clerk Maxwell in 1864
D) Isaac Newton in 1704

Question

Quizplus · Accepted Answer

Ole Rømer was the first to demonstrate that light had a finite speed, based on observations of the eclipses of Jupiter's moon Io. His observations in 1675 showed that the time between eclipses seemed to be shorter when Earth was moving towards Jupiter and longer when Earth was moving away. He correctly attributed this effect to the finite speed of light.

Who First Showed That Light Does NOT Travel at Infinite