(6.1.4) - Forced Vibration & Resonance Flashcards
What is resonance?
- Driving frequency = Natural frequency (f = f0)
- Amplitude is at a max
What is a free oscillation?
A system oscillates on its own without continuous external force
What is a forced oscillation?
A system is subjected to a periodic external force
What is Natural Frequency?
The frequency at which a system naturally oscillates when disturbed and left alone (damping = 0)
What is it, what direction it acts in
What is Damping?
- Resistive force
- Always opposite direction to velocity (reduces amplitude)
What is Driving Frequency
The frequency of the driving force
Describe peak, describe resonant frequency relative to natural frequency
No damping in resonance
- Very high and sharp peak
- Resonant frequnecy = natural frequency
Describe peak, describe resonant frequency relative to natural frequency
Light damping in resonance
- High and sharp peak
- Resonant frequency is slightly lower then natural frequency
Describe peak, describe resonant frequency relative to natural frequency
Heavy damping in resonance
- A relatively low and broad peak
- Resonant frequency is much lower then natural frequency
Describe peak, describe resonant frequency relative to natural frequency
Critical damping in resonance
- No peak
- No resonance occurs
2 examples of Mechanical Resonance
- Car suspension
- Tuning fork
What happens to amplitude-
As damping increases
Amplitude decreases
