In the diagram shown,the difference in the height of the liquid columns in the two tubes of the manometer is $5\, cm$. The cross-sectional areas of the tube at $A$ and $B$ are $6\, mm^2$ and $10\, mm^2$ respectively. The rate at which water flows through the tube is ........ $cc/s$ $(g = 10\, m/s^2)$.

Consider a completely full cylindrical water tank of height $1.6 \ m$ and cross-sectional area $0.5 \ m^2$. It has a small hole in its side at a height $90 \ cm$ from the bottom. Assume the cross-sectional area of the hole to be negligibly small as compared to that of the water tank. If a load of $50 \ kg$ is applied at the top surface of the water in the tank,then the velocity of the water coming out at the instant when the hole is opened is ......... $m/s$ $(g=10 \ m/s^2)$.

Water is flowing in a conical tube as shown in the figure. The velocity of water at area $A_2$ is $60 \,cm/s$. The values of $A_1$ and $A_2$ are $10 \,cm^2$ and $5 \,cm^2$ respectively. The pressure difference between the two cross-sections is: (in $\,N/m^2$)

$A$ fully loaded Boeing aircraft has a mass of $5.4 \times 10^5 \, kg$. Its total wing area is $500 \, m^2$. It is in level flight with a speed of $1080 \, km/h$. If the density of air $\rho$ is $1.2 \, kg/m^3$,the fractional increase in the speed of the air on the upper surface of the wing relative to the lower surface in percentage will be $(g = 10 \, m/s^2)$.

What is an aerofoil? Explain.

$A$ scent sprayer is based on