Arun
Last Activity: 6 Years ago
Dear Vaibhav
Surface energy is defined as the amount of the work done against the force of surface tension, in forming the liquid surface of a given area at a constant temperature.
To obtain a expression for surface energy, take a rectangular frame ABCD having a wire PQ which can slide along the sides AB and CD. Dip the frame in soap solution and form a soap film BCQP on the rectangular frame. There will be two free surfaces of film where air and soap are in contact.
Work done = S*a
If temperature of the film remains constant in this process, this work done is stored in the film as its surface energy
Regards
Arun(askIITians forum expert)