Surface Energy & Angle of Contact

 Surface Energy:-  Free surface of the liquid to contract in order to have minimum surface area. So, some work is required to be done to increase the area of the free surface of the liquid. This work is done appears as potential energy stored in the increased area, called its surface energy.



Angle of Contact:- The surface of liquid near the solid surface is curved. The angle of contact between liquid and solid in contact is defined as the angle enclosed between the tangent to the liquid surface at the point of the contact  and the solid surface inside the liquid.

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