Recent content by BiotFartLaw

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    Help with finding normal modes of a bar swinging on a string

    Thanks. A new question though: What is ω (from the rotational KE) in terms of the two angles? Usually \omega = dot{\theta} . But that's only for one angle. Because if ω isn't in terms of the angle(s) then the rotational KE drops out when you take the derivatives for L which doesn't seem...
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    Help with finding normal modes of a bar swinging on a string

    Homework Statement A bar with mass m and length l is attached at one end to a string (also length l) and is swinging back and forth. Find the normal modes of oscillation. Homework Equations L=T-U, and the Lagrange-euler equation, I=(1/12)ml^2The Attempt at a Solution So my idea is this. Use...
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    Finding energy as a function of Symplectic area?

    Homework Statement Find the energy E of the harmonic oscillator (H(x,p)=p2/2m+mω2x2) as a function of the system's symplectic area. Homework Equations Canonical equations and A=\int p dx (over one period) The Attempt at a Solution From Hamilton's equations I get ...
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    Uncertainty of coherent states of QHO

    Homework Statement What is the uncertainty in x and p of the coherent state |z> = e^{-|z|^2/2} \sum\frac{z^{n}}{\sqrt{n!}} |n> Homework Equations ... The Attempt at a Solution This seems pretty straight-forward to me. You just find the expected value of (let's say) x...