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Bohr Model

  1. Nov 18, 2006 #1
    Hi; I got a question related to Bohr's model but I'm not sure how to interpret the equations given what I know. Here's the question, sorry if it's a long read:

    The Bohr model correctly predicts the main energy levels not only for atomic hydrogen but also for other "one-electron" atoms where all but one of the atomic electrons has been removed, such as in He+ (one electron removed) or Li++ (two electrons removed).

    (a) The negative muon (–) behaves like a heavy electron, with the same charge as the electron but with a mass 207 times as large as the electron mass. As a moving muon– comes to rest in matter, it tends to knock electrons out of atoms and settle down onto a nucleus to form a "one-muon" atom. For a system consisting of a lead nucleus (Pb208 has 82 protons and 126 neutrons) and just one negative muon, predict the energy (in electron volts) of a photon emitted in a transition from the first excited state to the ground state. The high-energy photons emitted by transitions between energy levels in such "muonic atoms" are easily observed in experiments with muons.

    (c) Calculate the radius of the smallest Bohr orbit for a – bound to a lead nucleus (Pb208 has 82 protons and 126 neutrons). Compare with the approximate radius of the lead nucleus (remember that the radius of a proton or neutron is about 10–15 m, and the nucleons are packed closely together in the nucleus).

    Appreciate any help =]
  2. jcsd
  3. Nov 20, 2006 #2


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    Homework Helper

    Start here


    and then follow the link to the "Bohr model" in the first line. Scroll to the "Classical Electron Orbit" and "Bohr Orbit" panels. Everything you need about the mass of the orbiter, the charge of the nucleus, the quantization of energy levels, and the energy of photons is there.
  4. Nov 10, 2007 #3
    I was wondering if someone could help me with this problem, I was looking it over and still dont understand how to solve it.
  5. Nov 11, 2007 #4
    please someone.
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