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Question
Define surface tension and surface energy.
Solution
a. Surface tension is defined as the force per unit length acting at right angles to an imaginary line drawn on the free surface of liquid.
b. The extra energy that a liquid surface holds under isothermal condition is called surface energy.
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'n' droplets of equal size of radius r coalesce to form a bigger drop of radius R. The energy liberated is equal to...................
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