As the temperature of water increases,its viscosity

What is viscous force? On what factors does viscous force depend?

$A$ 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

Water in a river $20 \ m$ deep is flowing at a speed of $10 \ ms^{-1}$. The shearing stress between the horizontal layers of water in the river in $Nm^{-2}$ is (Coefficient of viscosity of water $= 10^{-3} \ SI \ units$)

$A$ square plate of $0.1 \; m$ side moves parallel to a second plate with a velocity of $0.1 \; m/s$, both plates being immersed in water. If the viscous force is $0.002 \; N$ and the coefficient of viscosity is $0.01 \; \text{poise}$, the distance between the plates in $m$ is: