Fluid MechanicsMedium
Question
Air is streaming past a horizontal aeroplane wing such that its speed is 120 m/s over the upper surface and 90 m/s at the lower surface. If the density of air is 1.3 kg/m3 and the wing is 10 m long and has an average width of 2 m, then the difference of the pressure on the two sides of the wing is :-
Options
A.40.95 N/m2
B.409.5 N/m2
C.4095 N/m2
D.40950 N/m2
Solution
Using Bernoulli′s theorem
P1 +
ρv12 + ρgh1 = P2 + 
ρv22 + ρgh2
For the horizontal motion of the plane h1 = h2, then
P1 +
ρv12 = P2 + 
ρv22
or P2 - P1 =
ρ(V12 - V22)
=
× 1.3[1202 - 902]
= 0.65[210 × 30] = 4095 N/m2
P1 +
ρv12 + ρgh1 = P2 + ρv22 + ρgh2For the horizontal motion of the plane h1 = h2, then
P1 +
ρv12 = P2 + ρv22or P2 - P1 =
ρ(V12 - V22)=
× 1.3[1202 - 902]= 0.65[210 × 30] = 4095 N/m2
Create a free account to view solution
View Solution FreeMore Fluid Mechanics Questions
A water tank stands on the roof of a building as shown in the figure. Then the value of h for which the distance covered...If in the above problem the sphere is slightly displaced vertically from its equilibrium position, the time period of th...A wooden block is floating on the surface of water with its (1/4)th portion outside water. Its relative density and appa...A cubical block of density $\rho_{b} = 600\text{ }kg/m^{3}$ floats in a liquid of density $\rho_{e} = 900\text{ }kg/m^{3...Spherical balls of radius R are falling in a viscous fluid of viscosity η with a velocity v. The retarding viscous ...