3A50.XX Damped Simple Pendulum
Damped harmonic oscillator, eddy currents
A strong permanent magnet acts as a simple pendulum, swinging back and forth while hanging from strings. A copper plate underneath the magnet can be moved up to tune the eddy current damping.
-  Magnet on strings
-  Copper plate on a wooden block
-  Lab jack
-  Lab stand
-  90-degree clamp
-  Aluminum rod
- Clamp rod to lab stand.
- Hang magnet on rod.
- Danger! Strong magnets may disrupt pacemakers!
- Strong magnets can pinch fingers.
- Strong magnets may erase magnetic memory and magnetic stripes on credit cards.
- Swing the magnet to show the undamped motion.
- Place the lab jack and copper plate under the magnet.
- Swing the magnet to show the damped motion.
- Adjust the lab jack height for a different level of damping and repeat.
- PIRA 3A50.XX
- Don't attempt this at home!
If you have any questions about the demos or notes you would like to add to this page, contact Ricky Chu at ricky_chu AT sfu DOT ca.