3. Simple Harmonic Motion Flashcards
Amplitude of an Oscillation
The maximum displacement of an oscillating object from its equilibrium position
Free Oscillations
Oscillations with constant amplitude and no frictional forces
Frequency of Oscillations
The number of cycles per second made by an oscillating object (Hz)
The phase difference for two objects oscillating at the same frequency:
2πΔt/T where Δt is the time between successive instants when the two objects are at maximum displacement
Simple Harmonic Motion
Oscillating motion in which the acceleration is proportional to the displacement and always in the opposite direction to the displacement
Equilibrium Position
The lowest point in an oscillation where the objects stays when it’s still and stable
Restoring Force
A force that acts towards the equilibrium
Restoring force of a spring?
-kx where k is the spring constant and x is the displacement from the equilibrium position
The restoring force of a simple pendulum?
-mg sin θ where sin θ = s/L
as long as θ does not exceed about 10 °
(where s is the arc length of the displacement of the pendulum bob )
Dissipative Forces
Forces that cause the amplitude of an oscillating object to decrease as the energy of the system is dissipated to the surroundings as thermal energy.
Damped Oscillations
Oscillations that reduce in amplitude due to the presence of resistive forces such as friction and drag
Light Damping
The displacement of of the oscillating system decreases gradually with time, reducing by the same fraction each cycle.
Critical Damping
The oscillating object returns to equilibrium in the shortest possible time without overshooting
Heavy Damping
The damping is so strong that the displaced object returns to equilibrium much more slowly but no oscillating motion occurs
Natural Frequency
The frequency of free oscillations of an oscillating system
