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A man is rowing a boat with a constant v...

A man is rowing a boat with a constant velocity `v_(0)` in a river. The contact area of boat is `'A'` and coefficient of viscosity is `eta`. The depth of river is `'D'` . Find the force required to row the boat.

Text Solution

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`F-F_(T)=ma_(res)`
as boat moves with constant velocity `a_(res)=0`
`F=F_(T)`
We know `F_(T)=etaA(dv)/(dv), but (dv)/(dy)=(v_(0)-0)/D=(v_(0))/D`

then `F=F_(T)=(etaAv_(0))/D`
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