nn 2 سال قبل
What is speed of light in air and vacuum?
۳۰۰ million m/s
Speed of light in a vacuum and air = ۳۰۰ million m/s or 273,400 mph. Speed of light in water = 226 million m/s or 205,600 mph. Speed of light in glass = 200 million m/s or 182,300 mph. Because light travels so fast it is difficult to measure the change in its speed in different materials.