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Threshold Frequency

  1. Jun 1, 2009 #1
    Light of frequency 1.21e15 Hz illuminates a piece of tin, and the tin emits photoelectrons of maximum kinetic energy 1.96 eV. What is the threshold frequency of the metal?

    Planck's Constant*Frequency = (Planck's Constant)(Threshold Frequency) + Maximum Kinetic Energy

    1.21e15 = (6.63e-34)(x) + (1.96eV)
    (1.21e15-3.136e-19)/6.63e-34 = X
    Answer I got = 1.83e48Hz

    might be in the wrong section, I apologize if it is
  2. jcsd
  3. Jun 1, 2009 #2


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    On the LHS, you did not multiply frequency with Planck's Constant.

    It is alright other than that.
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