what is the speed of electromagnetic radiation, and how does it differ from frequency?

Answer 1

What is the speed of electromagnetic radiation? Light is one of electromagnetic radiation. All different electromagnetic radiation have the same speed in vacuum: c = 3x10^10cm/s
How does it differ from frequency? Speed and frequency are two different concepts. Frequency is the number of wave peaks at certain point in one second. Frequency tells how high energy the electromagnetic radiation is. For example, infrared, visible, and ultraviolet are all electromagnetic radiations, their speed is the same in vacuum. But ultraviolet has a higher energy than visible which is in turn higher than infrared.