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Homework Help: EM Wave direction and frequency

  1. Jul 24, 2005 #1
    hi guys i had a quick question about EM waves

    given EM travelling west, B field oscilates vertically and has f= 80,000 Hz and a rms strength of 6.75e-9 T what are the frequency and rms strength of electric field and what direction...

    so for direction i have it ocscillating horizontally and for rms strength i have E= cB

    so E = 2 v/m but for frequency i have no idea

    wavelength * f = v but i have no idea what wavelength is.... any help is appreciated thanks!
  2. jcsd
  3. Jul 24, 2005 #2
    you correctly solved the first questions
    you're very close to the "frequency" answer.
    how is the freq of the E field related to the freq of the B field in this EM wave?
    (hint: think "equal")

    also FYI:
    (frequency)*(wavelength) = velocity = c = 3x108 m/sec
    since you know that frequency = 80,000 Hz, you can also determine wavelength of this EM wave (altho it's not required for the problem solution)
  4. Jul 25, 2005 #3
    thanks for your help, i got it now, forgot that c=V thanks again
  5. Jul 25, 2005 #4
    actually, im kinda stuck again,,,,, if i used V=c,,, then i would get a wavelength of 3750m, and then when i try to find frequency of E field, i would get that it has the same frequency of B field, becuase A=B B=C
    A must = C
    A being B field frequency and C being E field frequency
  6. Jul 25, 2005 #5


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  7. Jul 25, 2005 #6
    ...i GUESS i can live with it...lol...............thanks guys
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