The speed of electromagnetic waves depends somewhat on the materialthrough which they're traveling. In vacuum (no material at all), the speed is 299,792,458 meters (186,282 miles) per second.
When photons collide with any matter, the radiation attenuates and energy is released as heat. There is variation in the ability of an electromagnetic wave to travel in a given medium, and its...
Electromagnetic waves can travel in a vacuum because this wave is a moving magnetic and electric field. These fields do not require a medium to travel in, and they "carry" the energy of the...