The Force of Surface Tension 

One way to describe Surface tension is as a force applied in the normal direction of a ray, whch are both in the plane of the fluid, the normal being directed in towards the fluid itself. this is shown visually in the book Capillarity and Wetting Phenomena: Drop, Bubbles, Pearls, Waves, by de Gennes, Brochard-Wyart and Quéré as this picture here:

The represents the direction and force applied to the bar in the given direction. l is the length of the rod and dx is the change from it's original position. There is an equation which actually represents this and gives you how it actually effects the world around you. This equation is given as δW = F*dx = 2γ*l*dx. This equation is broken down to say that the change in work is the same as the amount of force applied which can also be expressed as 2 times the surface tension of the fluid multiplied by the length of the rod and the change in distance. Perhaps a simpler way to give the relationship is that for each growth in any of the variables (Surface tension, the length of the rod or movement of the rod) the change in work is doubled. It could also be said that if the change in work is constant these variables are directly proportional to eachother.

 

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