$A$ small metal sphere is falling through a viscous liquid. The variation of velocity $(V)$ with time $(t)$ is shown correctly in which graph?

An air bubble of radius $r$ rises steadily through a liquid of density $\rho$ with velocity $v$. The coefficient of viscosity of the liquid is:

$A$ 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

Which of the following graphs best represents the motion of a raindrop?

$A$ spherical solid ball of volume $V$ is made of a material of density $\rho_1$. It is falling through a liquid of density $\rho_2$ $(\rho_2 < \rho_1)$. Assume that the liquid applies a viscous force on the ball that is proportional to the square of its speed $v$,i.e.,$F_{viscous} = -kv^2$ $(k > 0)$. The terminal speed of the ball is:

Eight identical drops of same radii are falling through air with steady velocity $6 \ cm/s$. If these drops coalesce,then the terminal velocity would be .......... $cm/s$.