Water flows steadily through a horizontal pipe of variable cross-section. If the pressure of water is $P$ at a point where flow speed is $v$,the pressure at another point where the flow speed is $2v$,is (Take density of water as $\rho$)

Why is Bernoulli's equation not applicable to turbulent flow? Explain.

$A$ liquid of density $600 \text{ kg/m}^3$ is flowing steadily in a tube of varying cross-section. The cross-section at a point $A$ is $1.0 \text{ cm}^2$ and that at $B$ is $20 \text{ mm}^2$. Both the points $A$ and $B$ are in the same horizontal plane,and the speed of the liquid at $A$ is $10 \text{ cm/s}$. The difference in pressures at $A$ and $B$ points is . . . . . . $\text{Pa}$.

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

Determine the pressure difference in a tube of non-uniform cross-sectional area as shown in the figure. $\Delta P = ?$ (in $Pa$)
$d_{1} = 5 \, cm, V_{1} = 4 \, m/s, d_{2} = 2 \, cm, V_{2} = ?$
Assume the fluid is water with density $\rho = 1000 \, kg/m^{3}$.

Air is blowing across the horizontal wings of an aeroplane in such a way that its speeds below and above the wings are $90\, m/s$ and $120\, m/s$ respectively. If the density of air is $1.3\, kg/m^3$,then the pressure difference between the lower and upper sides of the wings will be ........ $N/m^2$.