Tʜᴇ Sᴘᴇᴇᴅ ᴏғ ʟɪɢʜᴛ
8 - 11 electromagnetic waves never speed up or slow down if they do, the wave would die out speed of light - c, 2,999,792,458 m/s before 1600s , Johannes Kepler, Rene Descarte believe light to be transmitted instaneously Galileo Galilei first to question this viewpoint proposed experiment where 2 participants uncovered lanterns determine speed of light with distance limited by timekeeping methods and human reaction speed estimate light was at least 10x faster than speed in 1676, Danish astronomer Ole Romer noticed eclipses of Io happen later when Earth is father away and vice versa calculated speed of light to be 220,000,000 m/s around 1850 , French physicist Hippolyte Fizeau used cogwheel and mirror 8km apart obtain value of 313,000,000m/s for c in 1862 , fellow French Leon Fouca...