Question: what is the frequency (s-1) of electromagnetic radiation?
Answer: Electromagnetic radiation is made up of waves that are composed of photons which travel at the speed of light, c , in a vacuum, which is exactly 299,792,458 m/s, usually rounded to three significant figures as 3.00 x 108m/s . ... One wave—or cycle—per second is called a Hertz (Hz). 1 Hz = 1/s or s−1 .