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Rikin25
Apr9-08, 10:14 AM
1. The problem statement, all variables and given/known data

The roof of a house has an area of 92.8 m^2. In a violent storm the air blows across the roof at a speed of 106.8 km/hr.

2. Relevant equations

Assuming that the air has a density of 1.25 kg/m^3, what pressure difference is created by the storm between the air outside and inside the house?

3. The attempt at a solution

Pressure/s = Area * density / speed (m/s)
= 92.8 * 1.25 / (106.8/3.6)
= 3.91 atm*s

how do i find the time?
or am i doing the whole thing wrong?

Dr. Jekyll
Apr9-08, 11:44 AM
Maybe this has something to do with the Bernoulli's principle:

\frac{\rho v^{2}}{2}+\rho g h + p = const.

But then you don't need the surface...