Bernoulli's Equation: Finding the net force of wind blowing over a house

AI Thread Summary
To find the net force on a flat roof from wind blowing at 35 m/s, Bernoulli's equation can be applied. The pressure under the roof is stagnant, while the pressure above is influenced by the wind speed. The equation P1 + 1/2pv^2 indicates that the pressure difference leads to a net force acting on the roof. The area of the roof is 240 m^2, which can be used to calculate the force once the pressure difference is determined. Understanding the pressure dynamics is crucial for solving the problem effectively.
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Homework Statement


If wind blows at 35m/s over a house, what is the net force on the roof if its area is 240m^2 and is flat?

Homework Equations


P=F/A and P1 + 1/2pv^2 = constant

The Attempt at a Solution


I have no idea on how to find pressure, because if I sub it into P1 + 1/2pv^2 = constant, it wouldn't work because the pressures would turn out the same because the roof is flat.
 
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That's funny. I don't see a term for 'flat roof' in the Bernoulli equation.

However, look at the situation this way. The air under the roof is stagnant and has no velocity. The air above the roof is blowing with a velocity of 35 m/s.
What you are saying is that P1 + 1/2p*0 = P1 + 1/2p*35^2
 

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