$A$ liquid having a coefficient of viscosity $0.02 \, \text{decapoise}$ is filled in a container of cross-sectional area $20 \, m^2$. If the viscous drag between two adjacent layers in flowing is $1 \, N$, then the velocity gradient is ........ $s^{-1}$.

Consider a thin square plate floating on a viscous liquid in a large tank. The height $h$ of the liquid in the tank is much less than the width of the tank. The floating plate is pulled horizontally with a constant velocity $u_0$. Which of the following statements is (are) true?
$(A)$ The resistive force of liquid on the plate is inversely proportional to $h$
$(B)$ The resistive force of liquid on the plate is independent of the area of the plate
$(C)$ The tangential (shear) stress on the floor of the tank increases with $u_0$
$(D)$ The tangential (shear) stress on the plate varies linearly with the viscosity $\eta$ of the liquid

Explain velocity gradient and coefficient of viscosity and give their units.

$A$ flat plate of area $10 \, cm^2$ is separated from a large plate by a layer of glycerine $1 \, mm$ thick. If the coefficient of viscosity of glycerine is $20 \, \text{poise}$, the force required to keep the plate moving with a velocity of $1 \, cm/s$ is .......... $dyne$.

How does the coefficient of viscosity of a liquid and a gas depend on temperature?

$A$ cylindrical metal box whose flat surface has an area of $0.01 \ m^2$ rests on a liquid layer of $0.3 \ mm$ thickness. If upon applying a horizontal force of magnitude $\frac{1}{3} \ N$,the box slides with a constant speed of $0.09 \ m/s$,the coefficient of viscosity of the liquid is nearly: