In which direction is the velocity of a fluid particle at a point on a streamline directed?

$A$ 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

The blades of a windmill sweep out a circle of area $A$. If the wind flows at a velocity $v$ perpendicular to the circle,then the mass of the air of density $\rho$ passing through it in time $t$ is

Define laminar flow.

$A$ horizontal tube of non-uniform cross-section has radii of $0.1 \,m$ and $0.05 \,m$ respectively at $M$ and $N$. For a streamline flow of an incompressible liquid, the rate of liquid flow is

Explain the characteristics of streamlines.