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Homework Help: How many photons does it emit?

  1. Sep 11, 2007 #1
    a 1-kW raido transmitter operates at 880kHz. How many photons per second does it emit?

    Power=work/time
    Power=change in KE/time

    f=1/T
    T=1/880kHz

    so 1 kw=change in KE/1.136x10^-6

    change in KE=.00136 J

    i don't know if i am doing this right. please point me in the right direction.
     
  2. jcsd
  3. Sep 11, 2007 #2
    should i use the equation E(light)=hc/wavelength?

    what is h in this equation?
     
  4. Sep 11, 2007 #3
    should i use the equation E(light)=hc/wavelength?

    what is h in this equation?
     
  5. Sep 11, 2007 #4
    The energy of photon is:

    [tex] E=h\nu = hc/\lambda[/tex], h is Planck's constant (6.6x10^-34 Js or 4.1x10^-15 eVs)

    So everything that you should do is to divide the power of your transmitter (1 kW) with that energy E.
     
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