Mechanical Oscillations
Pendulums, free and forced oscillations, and resonance
Big Idea: An oscillation is a motion that repeats itself as a body swings back and forth around a stable equilibrium position. A restoring force always pulls the body back toward equilibrium, so it overshoots, comes back, overshoots the other way, and the cycle repeats. A swinging pendulum, a mass bouncing on a spring, a guitar string and the balance wheel of a watch are all mechanical oscillators.
By the end you will be able to:
- define amplitude, period, frequency and phase,
- read a displacement-time graph of a harmonic oscillation,
- use T = 2π√(L/g) for a mathematical pendulum and T = 2π√(m/k) for a spring,
- tell free oscillations from forced ones,
- explain resonance and where it helps or destroys.