Answer to Question #216009 in Mechanics | Relativity for Mubashar

Question

If

P1
and

P2
are the pressure above and below the wing of an aeroplane.

ρ
is the density of air,

A
is the area of the wing and

v1
and

v2
are the speeds of air above and below the wing. Then dynamic lift of aeroplane is

Answer 1

Given, Pressure - P_1, P₂

Speed - V₁, V₂

Area - A

Bernoulli's Law

If P₂ > P₁ & V₁ > V₂

F = P₁ + $\rho$gh + $\frac{1}{2}$$\rho$V₁²

P₁ + $\rho$gh₁ + $\frac{1}{2}$$\rho$V₁² = P₂ + $\rho$gh₂ + $\frac{1}{2}$$\rho$V₂²

P₂ - P₁ = $\frac{1}{2}$$\rho$V₁² - $\frac{1}{2}$$\rho$V₂²

A$\Delta$P = A[ $\frac{1}{2}$$\rho$(V₁² - V₂² ]

F = AP = A[ $\frac{1}{2}$$\rho$(V₁² - V₂² ]

Hence, A[ $\frac{1}{2}$$\rho$(V₁² - V₂² ] will be the dynamic lift of airplane.