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Homework Help: DeBroglie wavelength please help its due at 12am!

  1. Feb 7, 2005 #1
    The deBroglie wavelength of an electron which moves with a speed of .0320 c is
    7.18x10^-12

    What is the fundamental minimum uncertainty in a measurement of the position of the elctron in the previous prolem if its momentum is simultaneouslymeasured to a precisioin of plus or minus one percent (two percent total)?
     
  2. jcsd
  3. Feb 7, 2005 #2

    dextercioby

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    1.Compute "p_{x}".
    2.Compute \Delta p_{x}.
    3.Compute \Delta x from the HUP.

    Daniel.
     
  4. Feb 7, 2005 #3
    [tex]\Delta p \Delta x \geq \frac{\hbar}{2}[/tex]

    The problem states that the electron is moving .320 times the speed of light. The mass of the electron is known. The uncertainty in the momentum is .02p ([itex]\Delta p = .02 p = .02mv[/itex]).

    The only value in the above inequality you don't know is the uncertainty in position.

    --J
     
    Last edited: Feb 7, 2005
  5. Feb 7, 2005 #4

    dextercioby

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    1.Justin,the sign in the HUP is inverse than the one u posted... :tongue2:
    2.And it should be
    [tex] \Delta p_{x} \Delta x \geq \frac{\hbar}{2} [/tex]

    There's a huge difference between your (initial,in the case u edit it) formula and the one i've written.Can u see why...? :wink:

    Daniel.
     
    Last edited: Feb 7, 2005
  6. Feb 7, 2005 #5
    Those darned TeX letters confuzzled me! leq, geq, bah!

    --J
     
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