The velocity of a small ball of mass $M$ and density $d$,when dropped in a container filled with glycerine,becomes constant after some time. If the density of glycerine is $\frac{d}{2}$,then the viscous force acting on the ball will be:

$A$ person moves in sea water at terminal velocity wearing an electronic digital watch. What is the effect on the measurement of time by the waterproof watch?

$A$ 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 $\,m$)

What is the relation between poise and decapoise?

Eight equal drops of water are falling through air with a steady speed of $10\,cm/s$. If the drops coalesce,the new velocity is $.........\,cm/s$.

Two equal drops are falling through air with a steady velocity of $5 \, cm/s$. If these two drops coalesce,then the new terminal velocity will be ......... $cm/s$.