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Homework Help: Clarification of homework question meaning

  1. Mar 2, 2012 #1
    1. The problem statement, all variables and given/known data

    Suppose you measured the x-component of position of an electron to an accuracy
    matching it’s de Broglie wavelength, i.e., Δx = lambda/2. What is the relative
    uncertainty in the electron’s x-component of momentum, Δp/p?

    2. Relevant equations

    ΔxΔp >= h(bar)/2

    3. The attempt at a solution

    I just wanted to clarify that relative uncertainty is Δp, not Δp/p. My professor writes these questions and is currently sick, so I feel like he may have not been thinking completely clearly... I am finding Δp, and not the ratio Δp/p? I am pretty sure I merely need Δp.
  2. jcsd
  3. Mar 2, 2012 #2
    I'm pretty sure that your professor does want you to find what the relative uncertainty is (which is Δp/p).

    The key to this problem is that Δx depends on p.
  4. Mar 2, 2012 #3
    ooh, okay, I got it now, thanks!
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