3A50.76 - Water Piston
To demonstrate damped harmonic oscillations.
Dyed water will be poured into the bottom reservoir. Dyed water will also be placed into the glass tube that is held upside down exposing its mouth in a upward position. With careful execution, the holder of the now water filled tube must quickly and carefully tilt the glass tube around placing the mouth of the tube into the open reservoir of water. Secure the tube with a top and bottom 3-finger clamp attached to a tall stand. Secure the stand with a bench clamp if necessary to prevent the tube from falling over on accident or collision. A string may be attached to the tube and clamps in order to avoid breaking the tube upon dropping from too high of a height.
Lift the glass tube while being careful not to allow air into the tube breaking the partial vaccuum. Drop the tube from a safe height as in order to not break the tube. Watch while the water oscillates and comes to rest in an underdamped system.
The body of water in the reservoir and glass tube acts as the mass in a spring-damped oscillation system. The partial vaccuum in the glass tube acts as the dampener, while the normal atmospheric pressure on the exposed body of water acts as the spring. The system is considered "underdamped".