Mechanical Prop...

The velocity of the wind over the surface of the wing of an aeroplane is 80 ms$$^{-1}$$ and under the wing 60 ms$$^{-1}$$. If the area of the wing is 4m$$^{2}$$, the dynamic lift experienced by the wing is [ density of air $$=$$ 1.3 kg. m$$^{-3}$$]:

There is a hole at the side-bottom of a big water tank. The area of the hole is $$2\ mm^{2}$$. Through it, a pipe is connected. The upper surface of the water is $$5\ m$$ above the hole. The rate of flow of water through the pipe is ( in $$m^{3}s^{-1}$$) ( $$g= 10 \ ms^{-2}$$)

The initial speed with which water strikes the ground in $$ms^{-1}$$ is:

Calculate the velocity of efflux of kerosene oil from an orifice of a tank in which pressure is $$4 atm$$. The density of kerosene oil $$= 720 kg m^{-3}$$ and $$1$$ atmospheric pressure $$= 1.013 \times 10^{5}N m^{-2}$$.

In a test experiment on a model aeroplane in a wind tunnel, the flow speeds on the upper and lower surfaces of the wing are $$70m s^{-1}$$ and $$63 ms^{-1}$$ respectively. What is the lift on the wing, if its area is $$2.5 m^{2}$$ ? Take the density of air to be $$1.3kg m^{-3}$$.

 The initial speed with which water flows out from the orifice in ms$$^{-1}$$ is (g $$=$$ 10ms$$^{-2}$$):

In a horizontal pipe line of uniform cross-section,pressure falls by $$5\ Pa$$ between two points separated by $$1\ km$$. The change in the kinetic energy per kg of the oil flowing at these points is :(Density of oil $$= 800\ kgm^{-3}$$)

A horizontal pipe of non uniform cross section has water flow through it such that the velocity is $$2ms^{-1}$$ at a point where the pressure is $$40 kPa$$. The pressure at a point where the velocity of water flow is $$3 ms^{-1}$$ is : ( in $$kPa$$)

A room has a window of area $$A$$. Out side of the room wind is blowing parallel to the window with a velocity $$v$$. If the density of air is $$\rho $$ , then the force acting on the window is: