The terminal velocity of a sphere of radius $3 \ mm$ falling in a viscous liquid is $10 \ cm/s$. The terminal velocity of a ball of radius $6 \ mm$ of the same material falling in the same liquid will be $...... \ cm/s$.

If the terminal speed of a sphere of gold (density $\rho_g = 19.5 \times 10^3 \ kg/m^3$) is $0.2 \ m/s$ in a viscous liquid (density $\rho_L = 1.5 \times 10^3 \ kg/m^3$),find the terminal speed of a sphere of silver (density $\rho_s = 10.5 \times 10^3 \ kg/m^3$) of the same size in the same liquid. (in $m/s$)

In an experiment to verify Stokes' law,a small spherical ball of radius $r$ and density $\rho$ falls under gravity through a distance $h$ in air before entering a tank of water. If the terminal velocity of the ball inside water is the same as its velocity just before entering the water surface,then the value of $h$ is proportional to: (ignore viscosity of air)

Small water droplets of radius $0.01 \,mm$ are formed in the upper atmosphere and falling with a terminal velocity of $10 \,cm/s$. Due to condensation, if $8$ such droplets are coalesced to form a larger drop, the new terminal velocity will be ........... $cm/s$.

Define Poise.

$A$ spherical ball is dropped in a long column of a highly viscous liquid. The curve in the graph shown, which represents the speed of the ball $(v)$ as a function of time $(t)$ is