C is only roughly 3x10^8 meters per second when traveling in a vacuum. Any interaction with matter slows it down, though usually only very slightly.
I believe the slowest light has ever been measured is 38mph (15.6 meters per second), achieved by firing a laser through sodium atoms held in a Bose-Einstein condensate (0.37 degrees Kelvin).
Pretty impressive, really.
In other words, the “if” statements are extremely important.
C is only roughly 3x10^8 meters per second when traveling in a vacuum. Any interaction with matter slows it down, though usually only very slightly.
I believe the slowest light has ever been measured is 38mph (15.6 meters per second), achieved by firing a laser through sodium atoms held in a Bose-Einstein condensate (0.37 degrees Kelvin).
Pretty impressive, really.
In other words, the “if” statements are extremely important.
c is by definition the speed of light in vacuum. You use another variable (usually v) if you want the speed of light in a given refractive medium.