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Homework Help: How to solve this problem? help

  1. May 18, 2010 #1
    how to solve this problem? :( help

    Hello, I have this questions which I am confused at, :( I cant figure out what equation to use to solve it :(

    given that the frequency of Barium is 6.25X10^14 Hz and the cutoff Potential is 0.10V find the Max Kenitic Energy, threshold frequencie and work function

    thanks a lot I would really appreciate the help :)
     
  2. jcsd
  3. May 18, 2010 #2

    rock.freak667

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    Re: how to solve this problem? :( help

    Well start with the cut off potential, ask yourself, what exactly is this quantity?

    If they said that the frequency of Ba is 6.25(1014)Hz, which frequency is this?
     
  4. May 18, 2010 #3
    Re: how to solve this problem? :( help

    asked myself, and couldnt answer it :(

    Is it possible that I should use the equation E=eV ?
     
  5. May 18, 2010 #4

    rock.freak667

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    Re: how to solve this problem? :( help

    Yes but do you know why you would use that equation?

    Wouldn't the cut-off potential be the potential difference needed to stop the electrons from being emitted?
     
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