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Homework Help: Electron microscope

  1. Feb 21, 2006 #1
    electrons in an electron microscope are accelerated form rest to a momentum making their wavelength 0.06 nm.

    1. what is the voltage Vo needed for this?

    2. What is the final electron velocity?

    For 1.

    [tex]E=\frac{hc}{\lambda}=\frac{1240eVnm}{0.06 nm}[/tex]
    solve for E

    For 2.

    [tex]E=.5mv^2[/tex]
    Solve for v plugging in E from #1 and m=mass of electron

    is this the correct thought process?
     
  2. jcsd
  3. Feb 22, 2006 #2
    I think that the correct process for classical mechanic.
     
  4. Feb 22, 2006 #3
    i'm not sure I understand what you mean
     
  5. Feb 22, 2006 #4
    This is just a guess but I think he might mean relativistic corrections. I don't think those are absolutely neccessary because the electrons energy would be roughly 20keV which is still quite a bit smaller than it's rest energy.
     
  6. Feb 22, 2006 #5
    oh, you mean for part 2, i should use [tex]E=\sqrt{(pc)^2+(mc^2)^2}[/tex]?
     
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