Example

If the velocity distribution over a plate is given by

$u=\frac{2}{3}y-y^2$

in which is velocity in metre per second at a distance $y$

metre above the plate, determine the shear stress at $y=0$

and $y=0\mathrm{.}15m.$ Take dynamic viscosity of fluid as $8\mathrm{.}63$

poises.

In metric system,

$1$ Poise $=1g\frac{m}{c}m-sec$

In SI units,

$1$ Poise $=0\mathrm{.}1$ Pa$.$s