OU NanoLab/NSF NUE/Bumm & Johnson
Surface
Tension
•Fluids behave as though they
have a surface composed of an elastic skin which is always in tension. There are many manifestations of surface tension you can observe everyday. Here are some fundamental properties of surface tension.
•The force by a
planar soap film supported on a rectangular
frame with one movable bar of length l. The factor of two is introduced because the soap film has two surfaces.
Fs
l
•The work required to create new surface area.
Fs
Fw
d
2A
surface
tensionà
γ
unitsà force/length à typically given in
dyne/cm