The speed of a ball of radius $2 \,cm$ in a viscous liquid is $20 \,cm / s$. What will be the speed of a ball of radius $1 \,cm$ in the same liquid (in $\,cm / s$)?

$A$ ball of mass $m$ and radius $r$ is gently released in a viscous liquid. The mass of the liquid displaced by it is $m'$ such that $m > m'$. The terminal velocity is proportional to

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 the measurement of viscosity of liquids using terminal velocity experiment, spherical balls of same radius but having different densities are used. The variation of the terminal velocity $(v)$ with the ratio of density of spherical ball $(\sigma)$ to density of the liquid $(\rho)$, is best represented by :

$A$ small spherical solid ball is dropped in a viscous liquid. Its journey in the liquid is best described by which curve in the figure?

Spherical balls of radius $r$ are falling in a viscous fluid of viscosity $\eta$ with a velocity $v$. The retarding viscous force acting on the spherical ball is