- Sections
- A. General Materials & Mathematics
- B. Statics
- C. Kinematics & Dynamics
- D. Rotational Mechanics
- E. Gravitation & Astronomy
- F. Fluid Mechanics
- G. Vibrations & Mechanical Waves
- H. Sound
- I. Thermodynamics
- J. Electrostatics & Magnetostatics
- K. Electromagnetic Principles
- L. Geometrical Optics
- M. Wave Optics
- N. Spectra & Color
- O. Vision
- P. Modern Physics
Surface Tension - Thread On Water
Purpose
To demonstrate how detergent decreases the surface tension of water.
Equipment
Glass dish with water, liquid dishwashing detergent, thread loop, overhead projector.
Suggestions
Keep the thread near the center of the dish; use only a small drop of soap solution.
Setup Time
5 min.
Images
Description
Fill a container with water and place it on the overhead projector. Place a loop of thread on top of the water such that it forms an irregular shape. A drop of detergent solution gently placed inside the loop with the eyedropper reduces the surface tension of the water inside the loop. The greater surface tension outside the loop then pulls the thread outward into a uniform circle.
References
Ernest K. Chapin, Surface Tension and Floating Bodies, AJP 24, 178 (1956). ◙Ernest K. Chapin, The Strange World of Surface Film, TPT 4, 271-275, 286 (1966). ◙Richard Marble, Floating Objects, TPT 10, 67-68, (1972). ◙James T. Schreiber, Barroom Physics, Part II, TPT 13, 418-428, (1975).
-
See pagesf1. pressure in static fluids
-
See pagesf2. buoyancy
-
See pagesf3. surface tension
-
See pagesf4. fluid in motion
-
See pagesf5. pressure in moving fluids
-
See pagesf1. pressure in static fluids
-
See pagesf2. buoyancy
-
See pagesf3. surface tension
-
See pagesf4. fluid in motion
-
See pagesf5. pressure in moving fluids