Different heads are in Column - $I$ and their formulas are given in Column - $II$. Match them appropriately.

Column - $I$	Column - $II$
$(a)$ Velocity head	$(i)$ $\frac{P}{\rho g}$
$(b)$ Pressure head	$(ii)$ $h$
$(c)$ Potential head	$(iii)$ $\frac{v^2}{2g}$

$A$ large cylindrical tank of cross-sectional area $1\ m^2$ is filled with water. It has a small hole at a height of $1\ m$ from the bottom. $A$ movable piston of mass $5\ kg$ is fitted on the top of the tank such that it can slide in the tank freely without friction. $A$ load of $45\ kg$ is applied on the top of the water by the piston,as shown in the figure. The value of $v$ when the piston is $7\ m$ above the bottom is $(g = 10\ m/s^2)$ ....... $m/s$

Give the formula for the measurement of the velocity of a fluid in the broader part of a venturi-meter.

Two light balls are suspended as shown in the figure. When a stream of air passes through the space between them,the distance between the balls will

Consider a water tank as shown in the figure. Its cross-sectional area is $0.4\, m^{2}$. The tank has an opening $B$ near the bottom whose cross-sectional area is $1\, cm^{2}$. $A$ load of $24\, kg$ is applied on the water at the top. When the height of the water level is $40\, cm$ above the bottom,the velocity of water coming out of the opening $B$ is $v\, ms^{-1}$. The value of $v$,to the nearest integer,is ......$m/s$. [Take value of $g$ to be $10\, ms^{-2}$]

At a hydroelectric power plant,the water pressure head is at a height of $300\; m$ and the water flow available is $100\; m^{3} s^{-1}.$ If the turbine generator efficiency is $60\%,$ estimate the electric power available from the plant (in $MW$) $\left(g=9.8\; m s^{-2}\right).$