Question

What is the lift (in newtons) due to Bernoulli's principle on a wing of area 87 m2 if the air passes over the top and bottom surfaces at speeds of 260 m/s and 170 m/s respectively?

Answer 1

Step-by-step explanation:

According to Bernoulli's principle

P₁ + 1/2ρ v₁² + ρgh₁ = P₂ + 1/2ρ v₂² + ρgh₂ , ρ is density of air . P₁ , P₂ are pressures at two surfaces .

h₁ = h₂

P₁ - P₂ = 1/2ρ( v₂² - v₁² ) = Lift pressure

ρ of air = 1.225 kg / m³

P₁ - P₂ = 1/2ρ( v₂² - v₁² )

= .5 x 1.225 ( 260² - 170² )

= .5 x 1.225 ( 67600- 28900 )

= 23703.75 N/m²

Lift Force = pressure x area

= 23703.75 x 87

= 2062226.25 N .