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Homework Help: Help with classical mechanics

  1. Sep 19, 2005 #1

    My classical mechanics course is proving to be quite a challenge. The textbook has not arrived yet, and my professor has already assigned a problem set. For example, one question is

    A bead of mass m is constrained to move along a smooth conical spiral. The radius of the spiral ρ = a z and the angle along the spiral φ = - b z where ρ, φ and z are the standard cylindrical coordinates. Find the equation of motion of the bead.

    I have no idea where to start because we don't do any examples of worked problems in class, only theory and proofs. Does someone know any good online resources that I can check out?

  2. jcsd
  3. Sep 19, 2005 #2
    Essentially you can find z as a function of time. The rest are constraints. Write down the Lagrangian in terms of rho, phi and z, then substitute where applicable.
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