Periodic Motion 〰️ Flashcards
Damping
Oscillation energy lost to the environment = reduced amplitude
Light damping
Amplitude gradually decreases by a small amount each oscillation
Critical damping
Reduces amplitude to zero in the shortest possible time
Heavy damping
Amplitude reduces slower than critical but with no extra oscillation
Resonance
Where amplitude of oscillations of a system drastically increase due to gaining an increased amount of energy from driving force
Forced vibrations
Where a system experiences an external driving force which causes it to oscillate, the frequency of this driving force is significant
When does resonance occur
When driving frequency is equal to natural frequency of a system
Sharpness of resonance
Increases with an increase in damping and decreases with a decrease in damping
Damping on resonance
Increasing the damping will reduce the size (amplitude) of the oscillations at resonance, but the amount of damping has next to no effect at all on the frequency of resonance. Damping also has an effect on the sharpness of a resonance
Factors affecting resonance
Resonance is affected by several factors, including the natural frequency of the object or system, the damping present in the system, and the external forces acting on the system
Object in circular path at a constant speed
Constantly changing velocity as velocity has a magnitude and direction, therefore the object must be accelerating
Simple harmonic motion characteristic
Acceleration is directly proportional to its displacement
Angular speed EQ
w= v/r= 2pif
Centripetal acceleration EQ
a = v^2/r = mw^2r
Centripetal force EQ
F =mv^2/r = mwr^2
