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Homework Help: Help me get my 2.1 please!

  1. May 19, 2005 #1
    OK so I'm revising for my finals and have spent 14 hrs revising today and cannot for the life of me get the very last part of Qn 3 on the attached link.
    It begins "By minimising the potential energy........"

    Could someone throw me a lifeline and explain what I need to do because my exam's in less than 12 hours and I'm nearly OD'ing on ProPlus! :bugeye:

    Thanks a lot

    Attached Files:

  2. jcsd
  3. May 19, 2005 #2
    Ok, if you make a partial derivation respect to z and equal the result to zero, to minimize it; take off with the equality the constant pi and continue having ro, there put the argument that the integrand should be a constant (lambda) -the integration was over rdr - so you have the form requering, there you have actually directly the form of "a" and then go to pick the value required of lambda according to the problem . (put it more formal than me pls, i just taked a look)
    Last edited: May 19, 2005
  4. May 19, 2005 #3
    Yeah thats the one mate.
  5. May 20, 2005 #4


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    Sorry, hope you did ok on the test. How'd you do?
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