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For a surface molecule,...

For a surface molecule,

A

the net force on it is zero

B

there is a net downward force

C

the potential energy is less than that of a molecule inside

D

the potenital energy is more than that is molecule inside

Text Solution

Verified by Experts

The correct Answer is:
B, D
Consider the diagram where two molecules of liquid are shown. One is well inside the liquid and other is on the surface. The molecule (A) which is well inside experiences equal forces from all direction, hence net force on it will be zero.
And molecules on the liquid surface have some extra energy as it surrounded surrained by only half side of liquid molecules.
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