Exams › JEE Main › Physics
As a liquid is heated towards its critical temperature, the value of its surface tension tends to
- zero
- one
- infinity
- a negative number
Correct answer: zero
Solution
Surface tension arises from the cohesive forces at a liquid-vapour boundary. As temperature rises the interface weakens, and at the critical temperature liquid and vapour become indistinguishable, so the interface and its surface tension vanish.
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