3B10.16 Shive Wave Machine
Transverse waves, travelling waves, standing waves, damping, impedance, reflection, transmission
The shive wave machine is a torsional oscillator consisting of many rods attached to a twisting wire. Many aspects of waves can be seen with it, including travelling waves, wave speed, and reflection/transmission at interfaces. There are three oscillator segments available: one with long rods, one with short rods, and one that tapers smoothly between long and short rods.
-  Long-arm wave machine segment
-  Short-arm wave machine segment
-  Tapering-arms wave machine segment
-  Coupling clamp
-  Damping attachment
-  Hard stop
- Fold up the bases on the desired wave machine segments so that they stand up.
- Couple the bases together, if desired.
- Add damping and/or a hard stop, if desired.
- Do not apply sharp large-amplitude oscillations! This damages the machine.
In general, operation is straightforward: introduce gentle oscillations to the machine by hand, moving the end of a rod up and down. Instead of a script, here is a list of demonstrations to try:
- Travelling waves: single pulse excited by hand
- Standing waves: continuous wave excitation
- Wave speed: contrast a pulse through the short-arm segment and a pulse through the long-arm segment
- Damping: put the damping attachment on a rod and send in a travelling wave; damping can be adjusted by changing the position at which the attachment couples to the rod
- Reflection and phase shift: can put hard stop or not to illustrate the phase shift from reflections off of higher impedance media
- Reflection and refraction with impedance mismatch or discontinuity: attach short-arm and long-arm segments directly and send in a travelling wave; can be contrasted with short-arm and long-arm segments joined by the tapering-arms segment
- PIRA 3B10.16, 3B10.30, 3B22.30, 3B25.10, 3B25.20
- Can be purchased through Pasco, part numbers SE-9600 and SE-9601
- 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.