Simple Harmonic Motion Flashcards
Define ‘free oscillations’
Amplitude is constant. No friction is present.
Define ‘Amplitude’
The maximum displacement from equilibrium.
Define ‘time period’
Time for one complete cycle of oscillations
Define ‘frequency’
The number if oscillations per second (Hz)
What is the equilibrium position?
The position at which no resultant force acts upon the object. (Object is at rest).
State the two conditions for an object to oscillate with Simple Harmonic Motion
1) Acceleration is proportional to displacement
2) Acceleration is in the opposite direction to displacement.
What is the equation for the phase difference of two objects oscillating at the same frequency?
Pd (radians) = (2pi dt) / T
dt = time between successive instants that the objects are at maximum displacement.
What does the curve look like of a displacement time graph of SHM and UCM if Vo = 0ms-1?
cos graph.
What does the curve of a velocity time graph look like (for SHM if Vo= 0)?
Negative some graph. (Gradient of the displacement time cos graph)
What is the shape of the acceleration time graph of SHM and UCM if Vo=0?
Negative cos graph.
Gradient of the negative sine graph of velocity time.
What is the effect of changing the time period on the speed of oscillations?
Reduce time period, faster oscillations
Increase time period, slower oscillations.
What is the restoring force? What is it proportional to?
For any object in SHM, the resultant force is always towards equilibrium. This is called the restoring force.
The restoring force is proportional to the displacement.
For a mass-spring system T=2pi(m/k)^1/2
How can the frequency be reduced by changing m?
Adding extra mass
The inertia of the system increases
So T increases.
For a mass-spring system T=2pi(m/k)^1/2
How can the frequency be reduced other than by changing m?
using weaker springs. The restoring force will be weaker, so T will be less.
When does a Simple pendulum oscillate with Simple Harmonic Motion?
If the angle between the string and the normal is less than 10 degrees, the pendulum will oscillate with simple harmonic motion.
