The viscous force between two liquid layers is

$A$ metal block of base area $0.20\,m^2$ is placed on a table,as shown in the figure. $A$ liquid film of thickness $0.25\,mm$ is inserted between the block and the table. The block is pushed by a horizontal force of $0.1\,N$ and moves with a constant speed. If the viscosity of the liquid is $5.0 \times 10^{-3} \,Pa-s$,the speed of the block is $.........\times 10^{-3}\,m/s$.

The velocity of water in a river is:

Explain the velocity gradient and the coefficient of viscosity,and provide their units.

$A$ river $10\,m$ deep is flowing at $5\,m/s$. The shearing stress between horizontal layers of the river is :- $(\eta = 10^{-3}\,SI\,unit)$

$A$ metal cube of side $10 \,cm$ rests on a film of a liquid of thickness $0.2 \,mm$. If upon applying a horizontal force $\overrightarrow{F}$ of magnitude $0.1 \,N$ the cube slides with a constant speed of $0.08 \,m/s$, then the coefficient of viscosity is