A particle of mass kg moves on a line in the V-shaped potential

PHYSICS · Multi-part · Fermi University Physics · Mechanics & Dynamical Systems · Quantum Mechanics · Origins of quantum theory

Action and Symmetry, Ch Hamilton-Jacobi theory and action-angle variables

Problem

A particle of mass m=0.50m = 0.50 kg moves on a line in the V-shaped potential V(x)=F∣x∣V(x) = F|x|, with F=3.0F = 3.0 N, and has energy E=1.5E = 1.5 J. ((a)) Find its action variable I=12π∮p dxI = \dfrac{1}{2\pi}\oint p\,\mathrm{d}x as a function of EE, and evaluate it. ((b)) Invert the result to get H(I)H(I), and use ν=∂H/∂I\nu = \partial H/\partial I to find the angular frequency, first as a function of EE and then as a number. Check it against the period found directly from the motion under a force of constant magnitude FF. ((c)) Apply the Bohr-Sommerfeld rule I=nhP/2πI = nh_{\rm P}/2\pi to find how the allowed energies depend on nn, and evaluate E2/E1E_2/E_1. Compare with the oscillator, where E∝nE\propto n, and with a particle between hard walls, where E∝n2E\propto n^2.

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