Chapter 17 - Oscillations Flashcards
Angular Frequency
The magnitude of angular velocity.
What is simple harmonic motion (SHM)?
When an object oscillates with a constant time period even when the amplitude varies.
What is an isochronous oscillator?
An oscillator in which frequency & period are independent of amplitude.
At what point in an SH oscillator is velocity at its highest?
When displacement = 0
At what point in an SH oscillator is acceleration lowest?
At minimum displacement.
What is the relationship between kinetic and potential energy in SHM?
EK + EP = E total (constant)
When EK increases, EP decreases.
What is a damping force?
Any force that causes an oscillating system to lose energy.
What effect does light damping have on SHM?
Reduces amplitude, but not time period.
What effect does heavy damping have on SHM?
Reduces amplitude and noticeably changes time period.
What effect does very heavy damping have on SHM?
Stops the oscillation entirely.
What is the difference between a free and a forced oscillation?
No external forces act on a free oscillation, but there is a periodic driver force applied to a forced oscillation.
Natural Frequency
The frequency of a free oscillation.
Resonance
The increase in amplitude of a forced oscillation when natural frequency = driving frequency.
Give an example of how damping is used in real life.
Shock absorbers damp oscillations in cars.
Give an example of how forced oscillations are used in real life.
In an organ pipe, the column of air resonates, driven by the motion of air at the base.
