How to solve this problem?
The velocity of water in a river is 18km/hr near the surface . If the river is 5m deep, find the shearing stress between the horizontal layers of water. The coeffecient of viscosity of water = 10^-2poise

Question

How to solve this problem?
The velocity of water in a river is 18km/hr near the surface . If the river is 5m deep, find the shearing stress between the horizontal layers of water. The coeffecient of viscosity of water = 10^-2poise

priyar · Answer

@ParthKohli @imqwerty @ganeshie8

priyar · Answer

@UnkleRhaukus  can u help?

anonymous · Answer

assuming Couette flow tau = mu *dv/dy I think

priyar · Answer

@ScientistsAreHot i didn't get u?

baru · Answer

$$\tau = \mu \frac{dv}{dy}$$

is the formula @ScientistsAreHot is talking about

baru · Answer

the velocity at the bottom of the river is zero. you can assume that the velocity varies linearly from the bottom of the river to the top and write a function to give velocity at any height. the slope of this function is dv/dy. μ is viscosity.τ is shear stress.

priyar · Answer

i didn't know this formula...

priyar · Answer

how to write velocity as a function of ht @baru ?

baru · Answer

|dw:1454488197998:dw|

baru · Answer

V= (18/5) y

baru · Answer

sorry, you have to convert 18km/hr to m/s

priyar · Answer

ya i converted and multiplied by 0.1 since poise is 0.1kg(m)^-1(s)^-1
and i got the answer..! thanks a lot! can u help me with some more? i have tagged u..