The surface tension of a liquid is `5` Newton per metre. If a film is held on a ring of area `0.02 metres^(2)`, its surface energy is about :A. `5 xx 10^(-2) J`B. `2.5 xx 10^(-2) J`C. `2 xx 10^(-1) J`D. `3 xx 10^(-1) J`

The surface tension of a liquid is `5` Newton per metre. If a film is

1.	The surface tension of a liquid is `5` Newton per metre. If a film is held on a ring of area `0.02 metres^(2)`, its surface energy is about :A. `5 xx 10^(-2) J`B. `2.5 xx 10^(-2) J`C. `2 xx 10^(-1) J`D. `3 xx 10^(-1) J`
Answer» Correct Answer - C We know that surfaces energy `U_(s) = T xx Area`. Hence. As `2` films are formed because of ring. So `U_(s) = T xx 2 xx (A)` `= 5 (N)/(m) xx 2 xx 0.02 m^(2) = 0.2 J`

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The surface tension of a liquid is `5` Newton per metre. If a film is held on a ring of area `0.02 metres^(2)`, its surface energy is about :A. `5 xx 10^(-2) J`B. `2.5 xx 10^(-2) J`C. `2 xx 10^(-1) J`D. `3 xx 10^(-1) J`

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