3D40.31 Chladni Plate
Resonance, standing waves
A metal plate, with salt sprinkled on top of it, is mounted on a mechanical vibrator that is powered by a function generator. At specific frequencies, the salt accumulates at certain locations of the plate representing the standing wave patterns of the system.
-  Function generator
-  BNC-banana cable
-  Mechanical vibrator
-  Square metal plate
-  Round metal plate
-  Container of salt
-  Brush
-  Paper box-top
- Metal shims
-  Overhead earmuffs
- Disposable earplugs
- Place the mechanical vibrator in the paper box.
- Lock the vibrator.
- Place a plate on top of the mechanical vibrator.
- Unlock the vibrator.
- Connect the function generator to the mechanical vibrator.
- Level the plate by putting metal shims under the mechanical vibrator. If the plate is level, it should make fairly symmetric salt patterns at resonance. (Optional)
- Wear ear protection while driving the plate at high amplitude.
- Distribute earplugs to the students who want them. Advise the other students they may want to cover their ears.
- Sprinkle salt uniformly on top of the plate. Spread it around with the brush as required.
- Turn on the function generator.
- Adjust the frequency of the signal generator to a resonance.
- Remove excess salt with a brush, if required.
- Repeat 1-4 for other resonances.
- Repeat the experiment using the other plate.
- PIRA 3D40.31
- 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.