In the case of a fluid,Bernoulli's theorem expresses the application of the principle of conservation of :

Application of Bernoulli's theorem can be seen in

In a test experiment on a model aeroplane in a wind tunnel,the flow speeds on the upper and lower surfaces of the wings are $70 \,m/s$ and $65 \,m/s$ respectively. If the wing area is $2 \,m^2$,the lift of the wing is . . . . . . $N$. (Given density of air $= 1.2 \,kg/m^3$)

Blood velocity: The flow of blood in a large artery of an anesthetised dog is diverted through a Venturi meter. The wider part of the meter has a cross-sectional area equal to that of the artery,$A = 8 \; mm^2$. The narrower part has an area $a = 4 \; mm^2$. The pressure drop in the artery is $24 \; Pa$. What is the speed (in $m/s$) of the blood in the artery?

Glycerine of density $1.25 \times 10^3 \ kg/m^3$ is flowing in a conical-shaped horizontal pipe. The cross-sectional area of the pipe at its two ends is $10 \ cm^2$ and $5 \ cm^2$ respectively. The pressure difference between the two ends is $3 \ N/m^2$. The rate of flow of the liquid in the pipe is:

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 ......... $m/s$ $(g=10 \ m/s^2)$.