Concepts

Oscillation.

Overview

A U-tube is filled 2/3 full of water and plugged on one end. A rubber bulb is used to pump air into the plugged end, creating oscillations. As the large oscillations damp out, the meniscus continues to oscillate.

Details

Equipment

• [1] Glass U-tube
• [1] Lab stand
• [2] 90-degree clamp
• [2] 3-finger clamp
• [1] Block of foam
• [1] Rubber stopper
• [1] Rubber bulb
• Rubber tubing
• Coloured water

Classroom Assembly

1. Place lab stand on lectern shelf.
2. Place foam block on lab stand.
3. Attach 3-finger clamps to ring stand using 90-degree clamps.
4. Attach U-tube to lab stand using 3-finger clamps.
5. Attach bulb and rubber tubing to U-tube.
6. Fill U-tube 2/3 full with coloured water.
7. Plug end to be pumped with rubber stopper.

Important Notes

• Oscillation of the meniscus can only be seen close-up or using a video camera.

Script

1. Pump the water in the U-tube using the rubber bulb.
2. Discuss the oscillation of the water.
3. As the large oscillations damp down, point out that the meniscus continues to oscillate.

Additional Resources