A circular loop of a thin wire of radius `(7//pi)` cm is suspended from one arm of a balance . The plane of the loop is in contact with the surface of soap solution . If the pull on the loop due to surface tension is found to be ` 0.6 xx 10^(-3)` kg wt , then the surface tension of soap solution will be ,A. `11xx10^(-3)`N/mB. `21xx10^(-5)`N/mC. `21xx10^(-3)`N/mD. `41 xx 10^(-3)` N/m

A circular loop of a thin wire of radius `(7//pi)` cm is suspended fro

1.	A circular loop of a thin wire of radius `(7//pi)` cm is suspended from one arm of a balance . The plane of the loop is in contact with the surface of soap solution . If the pull on the loop due to surface tension is found to be ` 0.6 xx 10^(-3)` kg wt , then the surface tension of soap solution will be ,A. `11xx10^(-3)`N/mB. `21xx10^(-5)`N/mC. `21xx10^(-3)`N/mD. `41 xx 10^(-3)` N/m
Answer» Correct Answer - C ` T = F/(2xx2pir)=(6xx10^(-4)xxpixx10)/(4xxpixx7xx10^(2))=21 xx10^(-3) ` N/m

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