Calculating lift using bernoulli's equation

AI Thread Summary
To calculate lift using Bernoulli's equation, the pressure difference between the top and bottom surfaces of a wing must be determined, using the formula P1 + 1/2rv1^2 = P2 + 1/2rv2^2. The lift force can then be calculated with F = P/A, where P is the pressure difference. It is essential to recognize that the pressure on the bottom surface must exceed that on the top to generate lift. While the approach to solving the problem is conceptually correct, the significance of the "Bernoulli force" is often overstated, contributing to only about 6% of total lift in aviation. Understanding these principles is crucial for accurately applying Bernoulli's equation to lift calculations.
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Homework Statement



What is the lift (in Newtons) due to Bernoulli's principle on a wing of area...m^2 if the air passes over the top and bottom surfaces at speeds of ...m/sand ...m/s, respectively? I've given the values but I just want to know if I'm doing the problem right conceptually.

Homework Equations



P1 + 1/2rv1^2= P2 + 1/2 r v2^2
F=P/A

The Attempt at a Solution



Hello, can someone help me with the approach to this problem?
I tried solving for P2-P1 in Bernoulli's and then using that as P in F=P/A and solving for F. I realize that the pressure on the bottom has to be greater than the pressure on the top to create lift so that's why I did P2-P1.
 
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Yes, you are going about solving the problem correctly. It doesn't really matter whether you subtract P2 from P1 or vise versa. You just need the difference in pressure to find the "bernoulli force" and then you just say "it's upward."

By the way, just do the problem as they ask you, and then let yourself know that the "Bernoulli force" is way over-hyped, and does not account for any more than 6% of total lift force on an airplane.
 
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