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Homework Help: Calculating the velocity of electron

  1. Feb 4, 2010 #1
    1. Problem: If the de Broglie wavelength of an electron is 555nm, what is its velocity?

    2. Relevant equations
    - λ = h/mv

    3. Ok so i first did the amu-g conversion. so i got the mass of the electron is (9.13297 x 10^-28g), then i did nm-m conversion so (555 x 10^-9m) and i multiplied them and then divided by plancks constant but i got the wrong answer?
  2. jcsd
  3. Feb 4, 2010 #2


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    Gold Member

    You need to show more work then this. Also, if you're using SI units, you must convert to kg, not grams.
  4. Feb 4, 2010 #3
    nvm i got the answer. its (6.6262x10^-34Js)/((9.13297x10^-25kg)/(555x10^-9m))
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