Lift produced by a wing increases with air density at a given velocity. This statement is:

Lift produced by a wing increases with air density at a given velocity. This statement is:

• A. True
• B. False
• C. Depends on humidity
• D. Only at high Mach

Answer: (A)

Lift comes from dynamic pressure, which is 0.5 times air density times velocity squared. At a fixed velocity, increasing density raises dynamic pressure, so lift increases in direct proportion (L ∝ ρV^2 for a given wing area and lift coefficient). This is true in the common subsonic regime where the basic lift formula holds. Humidity can affect density a little, but its effect on lift is small; high Mach changes compressibility and Cl but does not negate the direct influence of density on lift. So the statement is true.

Lift comes from dynamic pressure, which is 0.5 times air density times velocity squared. At a fixed velocity, increasing density raises dynamic pressure, so lift increases in direct proportion (L ∝ ρV^2 for a given wing area and lift coefficient). This is true in the common subsonic regime where the basic lift formula holds. Humidity can affect density a little, but its effect on lift is small; high Mach changes compressibility and Cl but does not negate the direct influence of density on lift. So the statement is true.