Free And Forced Vibrations Flashcards
Define free vibrations
No transfer of energy to or from the surroundings
When do forced vibrations occur?
When there is an external driving force.
The frequency of the driving force is called…
The driving frequency.
If the driving frequency is much less than the resonant frequency, the two are…
In phase. (Phase difference = 90°)
Resonance occurs when…
Driving frequency = resonant frequency
Define damping.
When a system loses energy to its surroundings, usually due to frictional forces, like air resistance.
Describe the damping graphs.
Light damping - erratic fluctuation
Heavy damping - same as light but smaller amplitude
Critical damping - steep negative gradient before tending to zero
Over damping - slow negative gradient
How does damping affect resonance?
The more damped the system, the flatter the response (the smaller the amplitude).
How can damping improve performance?
Soundproofing absorbs sound energy that affects the quality of sounds being recorded.
Define resonance
The condition in which an object or system is subjected to an oscillating force having a frequency close to its own natural frequency
