Question:medium
Water is flowing on a horizontal fixed surface such that its flow velocity varies with \(y\) (vertical direction) as
\[
v = k\!\left(\frac{2y^2}{a^2}-\frac{y^3}{a^3}\right).
\]
If coefficient of viscosity for water is \(\eta\), what will be the shear stress between layers of water at \(y=a\)?
Water is flowing on a horizontal fixed surface such that its flow velocity varies with \(y\) (vertical direction) as
\[
v = k\!\left(\frac{2y^2}{a^2}-\frac{y^3}{a^3}\right).
\]
If coefficient of viscosity for water is \(\eta\), what will be the shear stress between layers of water at \(y=a\)?
Show Hint
Shear stress depends on velocity gradient:
\[
\tau=\eta\frac{dv}{dy}
\]
Not on velocity itself.
Updated On: Mar 23, 2026
- \(\dfrac{\eta k}{a}\)
- \(\eta ka\)
- \(\dfrac{\eta a}{k}\)
- None of these
Show Solution
The Correct Option is A
Solution and Explanation
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