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Homework Help: Help on 2 quantum mechanics of atoms problems

  1. Aug 5, 2004 #1
    A proton is traveling with a speed of (6.550+/- 0.010)e5 m/s. With what maximum accuracy can its position be ascertained.

    I know that p=mv and x=p/h but what do I do with the +/- 0.010, that is the part that confuses me.

    How many electrons can be in the n=6, l=4 subshell. I know that l is n-1, so that can be 5, and n=6, so can the atom have 5 electrons?
     
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  3. Aug 5, 2004 #2

    Tom Mattson

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    That's the uncertainty in the velocity.

    No. n is not the number of electrons in a shell, it's the energy level. You need to list out the quantum states and count them.
     
  4. Aug 5, 2004 #3
    Yes I know that 0.010 is the uncertainity of the velcoity, but how do I incorporate that into the equation?
     
  5. Aug 5, 2004 #4

    Tom Mattson

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    Sorry, but I'm not answering that one directly. You should be reading the book.

    Now think: What principle in quantum mechanics expresses a mathematical relationship between uncertainty in momentum and uncertainty in position?
     
  6. Aug 5, 2004 #5

    Gokul43201

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    x = p/h ? Not true ! Reread the part about the Uncertainty Principle.

    For a given value of 'l', how many values can 'm' take ? For each of these 'm', how many values of 's' can there be ?
     
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