An incompressible fluid flows steadily through a cylindrical pipe having radius $R$ at point $A$ and $\frac{R}{3}$ at point $B$ further along the direction of flow of liquid. If the velocity at point $A$ is $V$,then the velocity at point $B$ is:

$A$ water spray gun is attached to a hose of cross-sectional area $30 \text{ cm}^2$. The gun comprises $10$ perforations, each of cross-sectional area $15 \text{ mm}^2$. If the water flows in the hose with a speed of $50 \text{ cm/s}$, calculate the speed at which the water flows out from each perforation. (Neglect any edge effects)

Can two streamlines cross each other? Why?

The total area of cross-section is $0.25\,m^2$. If the blood is flowing at the rate of $100\,cm^3/s$,then the average velocity of flow of blood through the capillaries is ........ $mm/s$.

$A$ pipe having an internal diameter $D$ is connected to another pipe of the same size. Water flows into the second pipe through $n$ holes,each of diameter $d$. If the water in the first pipe has speed $v$,the speed of water leaving the second pipe is

Water is flowing continuously from a tap having an internal diameter $8 \times 10^{-3}\, m$. The water velocity as it leaves the tap is $0.04\, ms^{-1}$. The diameter of the water stream at a distance $8 \times 10^{-1}\, m$ below the tap is close to