Is the Bernoulli's equation for airplane wings using metric units correct?

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    Bernoulli's Law
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The discussion addresses the application of Bernoulli's equation to airplane wings using metric units. The equation for pressure difference is confirmed to be valid, as it represents dynamic pressure, which is a component of Bernoulli's principle. Concerns were raised about unit compatibility when using metric measurements, specifically kg/m^3 for density and m/s for velocity. It is clarified that the units do indeed work out correctly, aligning with the expected units of pressure (N/m^2). Overall, the equation is deemed correct when applied properly in the metric system.
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Hi everyone,

I read on a website that the Bernoulli's expression can be applied to airplane wings by using the equation:

Difference in pressure above and below wing
= 1/2 x air density x [(airflow velocity below wing)^2 - (airflow velocity above wing)^2]


I tried using it but the units don't seem to add up correctly when I use the metric system (kg/m^3 for density, m/s for velocity).
The website uses (slugs/ft^3) for density, and (ft/s) for velocity.

Can anybody tell me if this equation is correct?
 
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What they express is simply the difference in dynamic pressure. Dynamic pressure is the first term in the Bernoulli equation. This makes the assumptions that there is no friction, no potential energy change and no compressibility effects.

Since it is dynamic pressure, the units do work out.

\frac{1}{2}\rho V^2

\frac{kg}{m^3}\frac{m^2}{s^2}

\frac{kg*m^2}{m^3*s^2}

\frac{kg*m}{s^2}\frac{m}{m^3}

\frac{N}{m^2}
 
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