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How can expectation of position^2 be > L

  1. Nov 12, 2015 #1
    How can position^2 expectation be greater than the Length of "box"? I mean <x^2> = L^2 / 3. Say L=100m then we have <x^2> = 333m. How is this possible?
  2. jcsd
  3. Nov 12, 2015 #2


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    Why should it not be possible? After all, ##100^2>100##. In any case the square is not comparable to the length, as the units of one is square metres and of the other is only metres. The volume of a cube that is 10cm per side is more than 10 ##cm^3##.
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