Further Mechanics 2 Flashcards
Define simple harmonic motion
- motion where:
- acceleration is directly proportional to displacement
- acceleration is always acting in the opposite direction to displacement
Define a free vibration
the oscillation of an object with no transfer of energy to or from the surroundings
When is there maximum velocity for a simple pendulum?
when it’s at the equilibrium position
What is the relationship between time period and amplitude during simple harmonic motion?
time period is independent of amplitude
What is a forced vibration?
the oscillation of an object due to an external periodic driving force
Define damping
a force which causes an oscillating system to lose energy and so causes the amplitude of the object’s oscillations to decrease
What is light damping?
when the system settles in equilibrium after many oscillations
Give an example of light damping
a pendulum in air
What is critical(ly) damping?
when the system settles in equilibrium in minimum time
Give an example of a critically damped system?
a car suspension
What is heavy damping / overdamping?
when the system settles in equilibrium after a long time
What is resonance?
when the frequency of the driving force equals the natural frequency of the system, a large (increase in) amplitude is seen
What is the phase difference between the driving frequency and the natural frequency when the driving frequency equals 0?
0
What is the phase difference between the driving frequency and the natural frequency when the system is at resonant frequency?
π/2
What is the phase difference between the driving frequency and the natural frequency when the driving frequency tends to infinity / when the amplitude tends to zero?
π
