$A$ 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 $m/s$)

Two water pipes $P$ and $Q$ having diameters $2 \times 10^{-2} \ m$ and $4 \times 10^{-2} \ m$,respectively,are joined in series with the main supply line of water. The velocity of water flowing in pipe $P$ is

Explain steady flow.

The surface of water in a water tank of cross-sectional area $750 \,cm^2$ on the top of a house is '$h$' $m$ above the tap level. The speed of water coming out through the tap of cross-sectional area $500 \,mm^2$ is $30 \,cm/s$. At that instant, $\frac{dh}{dt}$ is $x \times 10^{-3} \,m/s$. The value of '$x$' will be:

What is a tube of flow?

Define laminar flow.