$A$ vessel completely filled with water has two holes $P$ and $Q$ at depths $2h$ and $8h$ from the top,respectively. Hole $P$ is a square of side $a$ and hole $Q$ is a circle of radius $r$. If the volume of water flowing out per second from both holes is the same,then the side $a$ of hole $P$ is:

Water is filled in a cylindrical vessel of height $H$. $A$ hole is made at height $z$ from the bottom, as shown in the figure. The value of $z$ for which the range $(R)$ of the emerging water through the hole will be maximum is:

$A$ closed pipe containing liquid showed a pressure $P_{1}$ by gauge. When the valve is opened,the pressure was reduced to $P_{2}$. The speed of water flowing out of the pipe is $[\rho = \text{density of water}]$

The top of a water tank is open to air and its water level is maintained. It is discharging $0.74\,m^3$ of water per minute through a circular opening of $2\,cm$ radius in its wall. The depth of the centre of the opening from the level of water in the tank is close to........ $m$

$A$ cylinder of height $h$ is filled with water and is kept on a block of height $h/2$. The level of water in the cylinder is kept constant. Four holes numbered $1, 2, 3$ and $4$ are at the side of the cylinder and at heights $0, h/4, h/2$ and $3h/4$ from the base of the cylinder, respectively. When all four holes are opened together, the hole from which water will reach the farthest distance on the plane $PQ$ is the hole number:

$A$ container is filled with water up to a height of $20 \ m$. If a hole is made at the bottom,what will be the velocity of the water coming out in $m/s$?