Question

On the upper and lower surfaces of the wing of an aeroplane, the speeds of the air are 90m/s and 72 m/s respectively. What's the lift on the wing if the it's area is 3.2 m². , given that the density of the air is 1.29 kg/ m³

Answer 1

Answer:

6020 N

Explanation:

Use Bernoulli equation to find the difference in pressure.

P₁ + ½ ρ v₁² + ρgh₁ = P₂ + ½ ρ v₂² + ρgh₂

Neglected difference in elevation:

P₁ + ½ ρ v₁² = P₂ + ½ ρ v₂²

P₁ − P₂ = ½ ρ (v₂² − v₁²)

P₁ − P₂ = ½ (1.29 kg/m³) ((90 m/s)² − (72 m/s)²)

P₁ − P₂ = 1880 Pa

The lift on the wing is therefore:

F = ΔP A

F = (1880 Pa) (3.2 m²)

F = 6020 N