$A$ tank with a small hole at the bottom has been filled with water and kerosene (specific gravity $0.8$). The height of water is $3\,m$ and that of kerosene $2\,m$. When the hole is opened,the velocity of fluid coming out from it is nearly ........ $ms^{-1}$. (Take $g = 10\,ms^{-2}$ and density of water $= 10^3\,kg\,m^{-3}$)

$A$ container of large uniform cross-sectional area $A$ is resting on a horizontal surface and holds two immiscible,non-viscous,and incompressible liquids of densities $d$ and $2d$,each of height $\frac{H}{2}$,as shown. The upper surface of the liquid with lower density is open to the atmosphere. $A$ small hole is made on the wall of the container at height $h$ $(h < \frac{H}{2})$. The initial speed of efflux of the liquid at the hole is:

For a container open to the atmosphere,derive the velocity of the liquid exiting a narrow hole in the container wall using Bernoulli's equation and obtain Torricelli's law.

Consider a water jar of radius $R$ that has water filled up to height $H$ and is kept on a stand of height $h$ (see figure). Through a hole of radius $r$ $(r << R)$ at its bottom,the water leaks out and the stream of water coming down towards the ground has a shape like a funnel as shown in the figure. If the radius of the cross-section of water stream when it hits the ground is $x$,then:

$A$ vessel of area of cross-section $A$ has liquid to a height $H$. There is a hole at the bottom of the vessel having area of cross-section $a$. The time taken to decrease the level from $H_1$ to $H_2$ will be:

$A$ large open tank has two holes in its wall. One is a square hole of side $a$ at a depth $x$ from the top and the other is a circular hole of radius $r$ at a depth $4x$ from the top. When the tank is completely filled with water,the quantities of water flowing out per second from both holes are the same. Then $r$ is equal to ..........