Total Energy of a movable pivot-pendulum system, and ω

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SUMMARY

The discussion focuses on the derivation of total energy for a movable pivot-pendulum system, specifically involving a pendulum of mass m2 with a movable pivot of mass m1. The key insight is that the energy expression resembles that of a simple harmonic oscillator, represented as 1/2 mv^2 + 1/2 kx^2. By identifying the coefficients corresponding to k and m, one can directly determine the oscillation frequency as the square root of k/m. The variables x and v are redefined in terms of the pendulum's length (l) and angular displacement (phi) and velocity (phi-dot).

PREREQUISITES
  • Understanding of simple harmonic motion and oscillation principles.
  • Familiarity with energy conservation in mechanical systems.
  • Knowledge of pendulum dynamics and mass distribution.
  • Basic calculus for interpreting derivatives and integrals in motion equations.
NEXT STEPS
  • Study the derivation of energy expressions in simple harmonic oscillators.
  • Explore the effects of mass distribution on pendulum dynamics.
  • Learn about the mathematical modeling of movable pivot systems.
  • Investigate the relationship between angular displacement and linear motion in pendulums.
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Physics students, mechanical engineers, and anyone studying dynamics and energy conservation in oscillatory systems.

Aliasa
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Homework Statement


This is not really a homework questions, just part of my notes confusing me a bit.

This is the derivation of total energy for a pendulum of mass m2 with movable pivot of mass m1.
I don't understand how frequency can be read off. What am I missing?

Homework Equations


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You can read off the frequency by noting that the form of the energy looks just like a simple harmonic oscillator. The energy of a simple harmonic oscillator is 1/2 mv^2 + 1/2 kx^2, right? And the oscillation frequency turns out to be the square root of k/m. So that's all that is happening, you just find the coefficient playing the role of k, and the coefficient playing the role of m, and read off the frequency. Form is powerful. (It might help to notice that what we normally call x is here l times phi, and what we normally call v is here l times phi-dot.)
 
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