Uhf radio wave - determine frequency

[flynostrich08]

Homework Statement

in a certain uhf radio wave, the shortest distance between postions at which the elctric an magnetic fields are zero is .34m. determine the frequency of this uhf radio wave

The Attempt at a Solution

i basically just divided (3x10^8)/.34 = (8.8x10^8) that is c/d=frequency
can anyone tell me if that is the correct way to approach the problem? thanks

 

[kuruman]

How is the "shortest distance between postions at which the elctric an magnetic fields are zero" related to the wavelength?

 

[flynostrich08]

i don't know

 

[collinsmark]

i don't know

You might want to start by sketching a simple sine wave on a piece of paper. Let y be the vertical axis and t be the horizontal axis.

y = Asin(2πt)

Plot the sine wave for a few periods. Make sure to count how many wavelengths you have drawn. Then count how many times the sine wave crosses the t axis. Compare the two.