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Homework Help: Calculating the number of photons in a wave

  1. Jan 16, 2012 #1
    1. The problem statement, all variables and given/known data

    I am trying to answer a relatively simple question. I have been asked to compare the number of Photons in 100W light bulb and a 100W FM Radio per second. Having crunched the numbers it appears that an FM Radio wave gives out more Photons per second than a light bulb. Is this correct?

    2. Relevant equations

    I have used E=hc/λ

    3. The attempt at a solution

    I come out at 2.87x10E20 for a light (Using yellow) and 5.03x10E36 for a radio (the power depends on the wavelength)
  2. jcsd
  3. Jan 16, 2012 #2
    You are correct and presumably in your calculation you found that the energy of A radio photon is much less than the energy of a visible light photon.
    A radio frequency is very much less than the frequency of visible light
  4. Jan 17, 2012 #3
    Thank you, I was being a dumb arse.
  5. Jan 17, 2012 #4
    No comment:rofl:
    except to say.... don't look at yourself like that.
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