An incompressible liquid flows through a horizontal tube as shown in the following figure. Then the velocity $v$ of the fluid is ....... $m/s$.

Water is flowing through two horizontal pipes of different diameters which are connected together. The diameters of the two pipes are $3\, cm$ and $6\, cm$ respectively. If the speed of water in the narrower pipe is $4\, m/s$ and the pressure is $2.0 \times 10^4\, Pa$,then the speed of water in the wider pipe is ........ $m/s$.

$A$ tube of length $L$ is shown in the figure. The radius of the cross-section at point $(1)$ is $2 \ cm$ and at point $(2)$ is $1 \ cm$. If the velocity of water entering at point $(1)$ is $2 \ m/s$,then the velocity of water leaving at point $(2)$ will be: (in $m/s$)

Explain streamlines and streamline flow.

Water falls from a tap,down the streamline. What happens to the cross-sectional area of the water stream?

$A$ liquid flows steadily through a cylindrical pipe having a radius $2R$ at point $A$ and radius $R$ at point $B$ farther along the flow direction. If the velocity at point $B$ is $4v$, what will be the velocity at point $A$?