An $L$-shaped glass tube is just immersed in flowing water such that its opening is pointing against the flowing water. If the speed of the water current is $v$,then

Water from a tap emerges vertically downwards with an initial speed of $1.0\,ms^{-1}.$ The cross-sectional area of the tap is $10^{-4}\,m^2.$ Assume that the pressure is constant throughout the stream of water and that flow is streamlined. The cross-sectional area of the stream,$0.15\,m$ below the tap would be: (take $g = 10\,ms^{-2}$ )

$A$ plane is in level flight at constant speed and each of its two wings has an area of $40 \,m^2$. If the speed of the air is $180 \,km/h$ over the lower wing surface and $252 \,km/h$ over the upper wing surface,the mass of the plane is . . . . . . $kg$. (Take air density to be $1 \,kg \,m^{-3}$ and $g=10 \,ms^{-2}$)

Air is streaming past a horizontal aeroplane wing such that its speed is $120\, m/s$ over the upper surface and $90\, m/s$ at the lower surface. If the density of air is $1.3\, kg/m^3$ and the wing is $10\, m$ long and has an average width of $2\, m$,then the difference of the pressure on the two sides of the wing is ........ $N/m^2$.

Water (of density $\varrho$) flows steadily through a horizontal pipe of variable cross-section. If the pressure of water is $P$ at a point where the flow speed is $V$,then the pressure at another point where the flow speed becomes $3V$ is:

Two immiscible liquids are filled in a conical flask as shown in the figure. The cross-sectional area is shown. $A$ small hole of area $a$ is made in the lower end of the cone. Find the speed of liquid flow from the hole.