# Electromagnetic Waves Frequency

sarvesh0303
I was watching the lectures on the MIT OCW course 5.111 where it was said that electromagnetic radiations are periodic variations of the electric field. Does it mean that when we are talking about electromagnetic radiation, frequency indicates how quickly do the electric fields change(their direction and magnitude).

Gold Member
Yes - a frequency of 1Hz means that there is one cycle of oscillation of the fields per second. A cycle is the period during which an oscillation goes through a complete range of values - up, down and back to the beginning. Frequency is 1/(time taken for one complete cycle). That goes for all forms of oscillation btw.

sarvesh0303
Thanks . And does amplitude represent the maximum magnitude the electric field can reach??? What really puzzles me is what the wavelength represents in this case.

Mentor
And does amplitude represent the maximum magnitude the electric field can reach???

Yes.

What really puzzles me is what the wavelength represents in this case.

It's the distance along the direction that the wave is traveling, between two points of maximum magnitude, or between two points of minimum magnitude.

sarvesh0303
Thanks a lot guys!!!