A2 Unit 17 Oscillations

9702

State the 2 conditions for an object to be in simple harmonic motion (SHM)

Magnitude of acceleration is proportional to displacement from equilibrium position

Direction of acceleration is always in opposite direction to displacement

State the equilibrium position for an object moving with SHM

Midpoint of its motion

What is the displacement for an object moving with SHM?

Distance and direction from equilibrium position

Define the time period for an object moving with SHM

Time taken for one complete cycle of oscillation

Give the equation for SHM

a = -𝜔²x

Give the equation for the displacement x of an object in SHM at time t

x = A cos 𝜔t

Give the equation for the velocity of an object in SHM

v = ±𝜔√A²-x²

Define damping

The process by which an oscillating object loses energy to its surroundings, caused by damping forces

Define free vibration

Oscillation that occurs with no transfer of energy to or from the surroundings at a frequency equal to the natural frequency

What are the only forces acting on a freely oscillating object?

Forces providing the resultant restoring force

Define forced vibration

Oscillation where a periodic external driving force is applied

Define the natural frequency of an object

The frequency at which it would vibrate if left to vibrate freely, with no damping or driving forces acting on it

Define resonance

Process by which a maximum in the amplitude of a forced oscillation is produced