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Fluid Mechanics by Pijush K Kundu Surface Tension as Energy per unit of Area
Surface tension can also be described as joules per square meter. It is measured as the amount of energy required to increase the surface area by on square meter. This especially the case when the fluid is taking on a spherical shape. The equation for this is given as the difference in pressure multiplied by the radii and divded by the sums of the radii. This looks like
for Fluid Mechanics by Pijush K Kundu
This referes to a generally spherical surface with regular density. The equation is given as the difference of the pressure inside and outside the object. The radius is the radius of the spherical shaped fluid and teh sigma is the surface tension. As a side note, This equation brings about some startling conclusions, if you will look, the surface tension is dependent on volume and pressure, these values are also proportional to temperature for perfect gasses.