lyshastighet
Lyshastighet, often denoted by the symbol c, is the speed at which light travels in a vacuum. This fundamental constant in physics is approximately 299,792,458 meters per second. It is the maximum speed at which all energy, matter, and information in the universe can travel. The speed of light is not only the speed of visible light but also the speed of all electromagnetic radiation, including radio waves, microwaves, infrared, ultraviolet, X-rays, and gamma rays.
The concept of a finite speed of light was first proposed in the 17th century and experimentally
When light travels through a medium other than a vacuum, such as water or glass, its speed