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Homework Help: Wavelength, frequency, and E field amplitude from magnetic field equation

  1. Apr 14, 2010 #1
    1. The magnetic field of an electromagnetic wave in a vacuum is B_z= ( 3.0 uT )*sin(( 1.00*107)x - omega*t) , where x is in m and t is in s.

    What is the wavelength and frequency of this magnetic wave? What is the amplitude of the E field?

    2. wavelength = 2pi/k
    frequency = f = 1/T = omega/2pi
    E = cB

    3. k = 1*107, so lambda = 2pi/k = 6.28*10-7

    How do I find frequency without knowing omega?

    How do I go about obtaining an actual value for E0? It doesn't seem like E =cB will be enough here...
  2. jcsd
  3. Apr 14, 2010 #2


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    How are the frequency and the wavelength related?

  4. Apr 14, 2010 #3
    Yeah I got frequency since I posted this from c = lamba*f but I'm stuck on E still
  5. Apr 15, 2010 #4


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    You need the amplitude of the E field and it is c times the amplitude of B. What is the amplitude of B?

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