SIMPLE HARMONIC MOTION Flashcards
What are the two criteria for SHM.
Acceleration is always towards equilibrium.
Acceleration is directly proportional to displacement.
What are the two time period equations.
T = 2pi ROOT m/k
T = 2pi ROOT L/g
Describe the energy changes of a Pendulum.
Starting at maximum displacement to the left it has max PE. Then to KE back towards equilibrium. Then to PE Then to KE and finally back to PE.
State the energy changes for mass on spring.
Similar to pendulum but there are two different types of PE. Starting at lowest point all energy is elastic strain energy. Then converted to Ke then GPE at the highest position. Back to Ke as it falls to equilibrium position and finally to Elastic strain energy.
What equation relates all energy changes In an oscillator.
Max gpe/max elastic strain energy = max ke = total energy.
Describe Damping.
A situation where energy is lost from an oscillating system so that the amplitude decreases with time.
Energy loss caused by frictional forces opposing motion.
Describe Heavy Damping.
No oscillations takes a long time to reach equilibrium.
Describe Light Damping.
Rate at which energy removed is low - oscillations continue for a long time before dying away.
Describe Critical Damping.
Oscillations die away in the Shortest time - typically 1 oscillation.
What is a resonant system?
A system that involves a driver that makes a driven oscillator oscillate at a set frequency.
Define Resonance.
Is when the driving frequency equals the natural frequency of the driven oscillator.
Define Natural frequency.
Is a frequency an object would oscillate at if not disturbed.
What happens when Damping is increased?
Reduced maximum amplitude at resonance.
Lowers natural frequency of oscillator.
Broader resonance peak.
