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Energy in photoelectric effect

  1. Dec 2, 2014 #1
    1. The problem statement, all variables and given/known data
    Find the speed of light using planck's constant measuring apparatus

    2. Relevant equations
    E=h(frequency)
    E=(h*c)wavelength

    3. The attempt at a solution
    Can I substitute E=mc2 and use the mass of electron in the equation?
     
  2. jcsd
  3. Dec 2, 2014 #2

    BvU

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    The template has "all variables and given/known data", but you have nothing there....

    E = mc2 has to do with the total energy of an electron, moving or at rest. Is that what you have available as a known datum ?
     
  4. Dec 3, 2014 #3
    No the known variables are only frequency , wavelength and planck's constant and I have to find speed of light.
     
  5. Dec 3, 2014 #4

    BvU

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    So your relevant equation should have been ##c = \lambda \; \nu ## ?
    (##\nu## = frequency)
     
  6. Dec 3, 2014 #5
     
  7. Dec 3, 2014 #6

    BvU

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    As I said,
    The template has "all variables and given/known data", but you have nothing there....

    So I don't know what are known values for you.

    I don't really see how planck constant measuring apparatus can contribute in this context, unless you assume h is known and you use the instrument to determine ##\nu##. Then you still need the wavelength...
     
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