Unit 4: Oscillations and Waves

Page 1

4.1 Oscillations

Simple Harmonic Oscillations

Oscillations are periodic motions which centre around an equilibrium position.

Special Harmonic Motion is a special type of oscillation, i.e.:

The simple pendulum

The spring-mass system, where the mass is initially displaced to produce a periodic motion around the equilibrium position.

An object undergoes SMH if:

Acceleration of the object is directly proportional to its displacement from its equilibrium position.

Acceleration is always directed towards the equilibrium position.

Conditions for SMH:

When a body is displaced from equilibrium, a restoring force must exist.

The magnitude of the restoring force must be proportional to the displacement of the body and acts towards the equilibrium.