Chapter 15 Oscillations In this chapter we will cover the following topics: Displacement, velocity and acceleration of a simple harmonic oscillator Energy of a simple harmonic oscillator Examples of simple harmonic oscillators: spring-mass system, simple pendulum, physical pendulum, torsion pendulum Damped harmonic oscillator Forced oscillations/Resonance (15-1)
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(degrees) (radians) sin In the small angle approximation we assumed that << 1 and used the approximation: sin We are now going to decide what is a “small” angle i.e. up to what angle is the approximation reasonably accurate? (degrees) (radians) sin 5 0.087 0.087 10 0.174 0.174 15 0.262 0.259 (1% off) 20 0.349 0.342 (2% off) Conclusion: If we keep < 10 ° we make less that 1 % error (15-8)
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Moving support (15-13)