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Alice in quantumland

  1. Feb 25, 2004 #1
    This was one of the bonus questions on my homework. Teacher says whoever gets it right, consider yourself a god or goddess. Can anyone help me solve this?

    Calculate the lowest possible energy for an electron confined in a cube of sides equal to 10pm, and a cube of sides equal to 1fm. The latter cube is about the size of a nucleus. What do your energies say about the chance of an electron being inside the nucleus? *Hint: Assuming that the uncertainty in the position of the electron is the length of a side of a cube, find the change in Energy (triangle E is symbol) for each cube.
  2. jcsd
  3. Feb 25, 2004 #2


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    From the appearance of [tex]\Delta E [/tex] I assume you have been given the uncertainty principles for energy and time and for momentum and length. To use the E,t one, you have to get a [tex]\Delta t [/tex] out of the box side length, and I suggest you allow your electron to have a maximum speed of c, so the time it would spend in crossing the box would be ...? And the [tex]\Delta E [/tex] for that [tex]\Delta t [/tex] would be...?
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