5.3 Oscillations

Equations & Definitions

Displacement

Distance from equilibrium position (positive or negative)

Amplitude

The maximum displacement

Period

Time taken to complete one full oscillation

Frequency

Number of complete oscillations per unit time

Phase difference

Difference in displacement between 2 oscillating objects or the difference in displacement of 1 oscillating object at different times

Antiphase

2 oscillating objects. 1 is at maximum positive displacement at the same time that the other one is at maximum negative displacement. Phase difference = 𝛑 rad

In phase

2 oscillating objects reach maximum positive or negative displacement at the same time. Phase difference = 0 rad

Angular frequency definition

Used to describe the motion of an oscillating object. Closely related to the velocity of an object in circular motion.

Angular frequency equations

ω=(2𝛑)/T or ω=2𝛑f

Simple harmonic motion definition

Oscillating motion. ω² is constant. Acceleration (a) is directly proportional to displacement (x). Acceleration acts in opposite direction to displacement (to the equilibrium point)

Simple harmonic equation

a=-ω²x

The rules of simple harmonic motion

1. Simple harmonic oscillator exhibit sinusoidal motion

2. Displacement is proportional to negative acceleration

3. Acceleration is always towards the equilibrium centre

4. Period is isochronous for all amplitudes (takes the same amount of time!)