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The length of needle floating on water i...

The length of needle floating on water is 2.5 cm. Calculate thhe added force required to pull the needle out of water `(T=7.2xx10^(-4)N//cm)`

Text Solution

Verified by Experts

The force of surface tension `F=Txx2l(because` Two free surface are there)
`impliesF=7.2xx10^(-2)xx2xx2.5xx10^(-2)=3.6xx10^(-3)N`
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