Free Oscillations
- A free oscillation is defined as:
A vibration with no external forces acting on it
- A free oscillation has constant energy and amplitude ie. no energy loss or gain
- An example of a free oscillation is a plucked guitar string
- It will vibrate for some time after it is plucked and released
- Free oscillators vibrate at a particular frequency
- This is called the natural frequency of the vibration
- Every oscillator has a natural frequency of vibration
- This is the frequency in which it vibrates freely after an initial disturbance
Motion of an Oscillator
- An experimental and graphical method can be used to observe the motion of a simple mass-spring system
- Tie a pencil together with the mass and set the mass in free oscillations by displacing it downwards slightly
- The oscillations will move the pencil up and down
- On a piece of graph paper, allow the pencil to trace the path of the oscillations by pulling the paper sideways as the mass-spring system oscillates up and down
- The oscillations will produce a curved, periodic graph
- This will decrease in amplitude as the mass-spring system slows down
