Applications of Bernoulli's Theorem

A wind with speed $50\text{ m/s}$ blows parallel to the roof of a house. The area of the roof is $300\text{ m}^2$. Assume that the pressure inside the house is atmospheric pressure. Density of air is $1.2\text{ kg/m}^3$. The magnitude of the force exerted by the wind on the roof will be

A plane is in level flight at constant speed and each of its two wings has an area of $40\text{ m}^2$. If the speed of the air is $180\text{ km/h}$ over the lower wing surface and $252\text{ km/h}$ over the upper wing surface, the mass of the plane is ___________ kg.

(Take air density to be $1\text{ kg m}^{-3}$ and $g = 10\text{ ms}^{-2}$)

In a test experiment on a model aeroplane in wind tunnel, the flow speeds on the upper and lower surfaces of the wings are $70\text{ ms}^{-1}$ and $65\text{ ms}^{-1}$ respectively. If the wing area is $2\text{ m}^2$, the lift of the wing is _________ $N$.

(Given density of air $= 1.2\text{ kg m}^{-3}$)

Venturimeter is used to

The venturi-meter works on:

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

Two light balls are suspended as shown in figure. When a stream of air passes through the space between them, the distance between the balls will

A wind with speed 40 m/s blows parallel to the roof of a house. The area of the roof is 250 m2. Assuming that the pressure inside the house is atmospheric pressure, the force exerted by the wind on the roof and the direction of the force will be $(\rho_{air} = 1.2\, kg/m^3)$

In the diagram shown, if the difference in the two tubes of the manometer is 5 cm, the cross section of the tube at A and B is 6 mm2 and 10 mm2 respectively. The rate at which water flows through the tube ( g = 10 ms${}^{-2}$)

Air of density 1.2 kg m$^{-3}$ is blowing across the horizontal wings of an aeroplane in such a way that its speeds above and below the wings are 150 ms$^{-1}$ and 100 ms $^{-1}$, respectively. The pressure difference between the upper and lower sides of the wings, is: