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Photoelectric Effect and electrons

  1. Oct 20, 2009 #1
    The answer key says the 450 nm (blue) light would make electrons with the most KE, which I get.
    But then it says that the yellow 560 nm light would shed more electrons, which makes no sense to me because I thought the # of e- only depended on the intensity of the light and the question says the same amt. of energy was delivered by each laser.
    Is the answer key wrong?
     
  2. jcsd
  3. Oct 20, 2009 #2

    mgb_phys

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    The number of electrons depends on the number of photons

    Yes, how is energy related to number of photons?
     
  4. Oct 20, 2009 #3
    ooohhh so for the same amount of energy to be transferred with the 560 nm light, more photons would have to be used?
    so more electrons would be released from the metal?
     
  5. Oct 21, 2009 #4

    mgb_phys

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    Yes for the same power,the laser with the longer wavelength generates more photons.
     
  6. Oct 21, 2009 #5
    that was a tricky question.
     
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