$A$ solid ball of volume $V$ is dropped in a viscous liquid. It experiences a viscous force $F$. If a solid ball of volume $2V$ of the same material is dropped in the same fluid,then the viscous force acting on it will be

An iron sphere of mass $20 \times 10^{-3} \ kg$ falls through a viscous liquid with terminal velocity $0.5 \ ms^{-1}$. The terminal velocity (in $ms^{-1}$) of another iron sphere of mass $54 \times 10^{-2} \ kg$ is (in $.5$)

$A$ steel ball is dropped in a viscous liquid. The distance of the steel ball from the top of the liquid is shown in the graph below. The terminal velocity of the ball is closest to .......... $m/s$.

Why do rain drops not possess a velocity greater than a certain limit? Explain.

$A$ small steel ball is dropped from a height of $1.5 \,m$ into a glycerine jar. The ball reaches the bottom of the jar $1.5 \,s$ after it was dropped. If the retardation in the glycerine is $2.66 \,m/s^2$, the height of the glycerine in the jar is about (acceleration due to gravity $g = 9.8 \,m/s^2$) (in $\,m$)

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