When the temperature increases,the viscosity of

$A$ Newtonian fluid fills the clearance between a shaft and a sleeve. When a force of $800$ $N$ is applied to the shaft,parallel to the sleeve,the shaft attains a speed of $1.5$ $cm/s$. If a force of $2.4$ $kN$ is applied instead,the shaft would move with a speed of ......... $cm/s$.

$A$ square plate of side $0.1 \, m$ moves over another plate with a velocity of $0.1 \, m/s$ in a liquid of viscosity $0.01 \, poise$. If the viscous force acting is $0.002 \, N$,what is the distance between the two plates (in $, m$)?

Write one practical use of viscosity.

Is viscosity a vector or a scalar?

Water is flowing steadily in a river. $A$ and $B$ are two layers of water at heights $40 \ cm$ and $90 \ cm$ from the bottom. The velocity of layer $A$ is $12 \ cm/s$. If the velocity of the water at the bottom is $0$,what is the velocity of layer $B$ (in $cm/s$)?