# Find frequency of electromagnetic waves

Can anyone give a solution or guidance about how to solve this.

In vacuum, the components of an EM wave are Ey = 50(V/m)cos[(5.00 m-1)x + ωt], Ex = 0, and Ez = 0. What is ω?

## Answers and Replies

blue_leaf77
Science Advisor
Homework Helper
Do you know the velocity of EM wave in vacuum?

No this is all the data that I have regarding the question.

blue_leaf77
Science Advisor
Homework Helper
The question doesn't give you the value of velocity because velocity of EM wave in vacuum is a universal value.

BvU
Science Advisor
Homework Helper
Hello xamy, a belated welcome to PF !

Please check out the guidelines. They exist for a good reason (for which , see the guidelines ). One good habit in PF is that posters are required to use the template and they have to show an attempt at solution, make an effort, etc. You show recidive in violating both requirements ! Someone should have corrected you earlier. Welcome nevertheless.

And in this case you think you are stuck in such an early stage that I can come up with some understanding, but not with an excuse.
Did you try googling speed of em wave in vacuum ?

Where are you in your education ? Do you know that e.g. light is an EM wave ? Do you know that the speed of light is an exactly defined constant ? All things that possible helpers might have been able to pick up if you would have posted a bit more verbose thread -- using the template, of course

 sorry for interfering, blue. I now leave this to you.

blue_leaf77
but without wavelength frequency can't be found

BvU
Science Advisor
Homework Helper
What is there in the problem statement you can use to pin down the wavelength ? Think of the concept wavelength, what it means. How is it defined ?

BvU
Science Advisor
Homework Helper
Sorry blue for interfering (for the second time, even after promising at the first interruption).

Dear xaml, do you now see the usefulness of the template and the guidelines ? Both helpers thought you were stuck at the speed and tried to help with hints to overcome that. But from post #6 it emerges that guidance is needed on another aspect of the exercise !

Hint: sketch the wave in some way you can imagine it ... (sorry for the third time, blue. I'll really quit now...)

blue_leaf77
Science Advisor
Homework Helper
No problem BvU, that's also a reminder for me to always keep the rule in mind even in the position of answerer.

without wavelength frequency can't be found
I guess you still don't have the grasp of how to describe wave in a mathematical language. In case you are too lazy to search in your textbook, just search for "wave" in wikipedia, it has all you need to understand a wave as the basic starting point.

BvU
Science Advisor
Homework Helper
So how is xamy doing ? We may seem a bit nerdy, but we wouldn't be here if we weren't prepared to help !
So: -- in case you need any further assistance -- how can we help ?