The property of a liquid by which it opposes the flow of itself is called ..........

There is a $1$ $mm$ thick layer of glycerine between a flat plate of area $100$ $cm^2$ and a big fixed plate. If the coefficient of viscosity of glycerine is $1.0$ $kg/(m \cdot s)$,then what force in $N$ is required to move the plate with a velocity of $7$ $cm/s$?

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

Define velocity gradient and give its unit. Also,write the dimensional formula of the velocity gradient.

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 $= 10^{-3} \ SI \ units$)

$A$ 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 .......... $dyne$.