How do wind and air pressure affect a house's roof?

[asheik234]

Homework Statement

A house has a roof with an area of 220 m2. Wind blows over the top with a speed of 10 m/s. The density of air is 1.29 kg/m2. The air inside the house is stagnant. Point A is just inside the roof, and point B is outside the roof at the same height.

(a) What is the difference in pressure (PA - PB) between points A and B?


(b) What force is applied to the roof by the inside air?

Homework Equations

This is where I'm stuck at

The Attempt at a Solution

I don't know what equations to apply here, they all involve mass, but that's not a given.

 

[gneill]

Have you studied the Venturi effect? Look it up.

 

[asheik234]

Have you studied the Venturi effect? Look it up.

Yes, I've studied it, but how does that apply here?

 

[gneill]

Yes, I've studied it, but how does that apply here?

Um, air flowing faster over roof than under roof... air pressure difference... area of roof...

 

[asheik234]

Um, air flowing faster over roof than under roof... air pressure difference... area of roof...

Oh yes, I realized that, but I don't know where to go from there, what equations should I use.

 

[gneill]

Oh yes, I realized that, but I don't know where to go from there, what equations should I use.

What equation pertains to the venturi effect? Look up venturi effect.

 

[rude man]

Check Bernoulli.