Science Lab Experiment: Surface Tension
Demonstration: Surface Tension
Object: To find the forces of surface tension.
Materials: thick wire, cotton thread, soap solution
Diagram:
Method: Form a thick piece of wire into a closed loop as shown
in the diagram. Tie a piece of cotton thread loosely across
the frame. Dip the whole loop into a beaker of soap solution
to form a film across the loop. Using a pencil point, try to
move the thread about in the soap film. With a stick of chalk
or the blunt end of a pencil, break the film on one side of the
film only.
Observations:The thread curves and a film covers the whole loop.
Conclusions:The soap forms a film because of surface tension.
It is concluded that if one side is broken, the other
will break as well, since it is a complete film.
