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प्रश्न
Prove that, equivalent S.I. unit of surface tension is J/m2.
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उत्तर
T = `F/L`
where F = Force (N), L = Length (m)
= SI unit of T = `N/m`
Surface tension can also be written as
T = `W/A`
where W = Work (J), A = Area (m2)
= SI unit of T = `J/m^2`
We know
1J=1N×1m
So,
`J/m^2 = (N * m)/m^2 = N/m`
Both units are the same
`1N/m equiv 1J/m^2`
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