What is the force exerted on a flat roofed building by wind pressure?

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To calculate the force exerted on a flat-roofed building by wind pressure, one must apply Bernoulli's equation, considering the pressure difference between the still air inside and the moving air outside. The wind speed is 12 m/s, and the density of the air is 1.29 kg/m^3. The roof area is 100 m^2, which is essential for determining the force from the pressure difference. The pressure outside the roof is lower due to the wind, while the inside pressure remains constant. Understanding these principles allows for the calculation of the force exerted on the roof.
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Homework Statement



"Wind (density=1.29kgm^-3) blows over a flat roofed building of height 20m at 12ms^-1.The area of he roof is 100m^2.What is the magnitude and direction of the force exerted on the roof if the pressure difference between inside and outside is due solely to the fact that the inside air is still?Assume laminar flow."


Homework Equations



Im really stumped with this Q, I have scanned the net and it seems to involve the Bernoulli Eqn , however, i don't really understand what's occurring, any help appreciated.





The Attempt at a Solution

 
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If you assume that the thickness of the roof is negligible, what's the pressure of the air just outside the roof, where the air is flowing? And the pressure inside where the air is stationary? So, what's the force due to the pressure difference?
 
thats the thing, i undererstand where the pressure difference comes from, but not how to calculate it based on the dimensions of the roof?...
 
The dimensions of the roof is needed to calculate the force due to the pressure difference. You need to use Bernoulli's equation to calculate the pressure difference. (Hint: The air inside is stationary, while outside, it's moving.)
 

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