# Wind load - is it a FORCE or PRESSURE?

1. Jun 11, 2010

### joeykeys

1. The problem statement, all variables and given/known data

Explain if wind on walls and roofs of buildings is considered a pressure or a force?

2. Relevant equations

P = F/A

3. The attempt at a solution

Wind load should be measured in terms of pressure?..but I don't know the exact reason why it is. Does it have something to do with "non-contact" force?..

Thanks for your time for the explaination!

2. Jun 11, 2010

### hikaru1221

Why do we have to consider wind as pressure or force, when it is defined as the flow of the gas, which means it is a phenomenon?

3. Jun 11, 2010

### joeykeys

Do you mean that measure of the flow of gas/liquid must be in term of "pressure" but not "force"?

4. Jun 11, 2010

### hikaru1221

No (I don't know why the word "pressure" was underlined).
You may describe the state of the flow at a point with many quantities, such as velocity of the element of the gas at that point, pressure of the gas, etc. Flow means motion, and so, it cannot be measured; it can only be described.

5. Jun 11, 2010

### joeykeys

How would you comment on the "wind load" on buildings then?
Is it a pressure but not a force?

6. Jun 11, 2010

### hikaru1221

I've just googled a little bit and found that people defined "wind load" as force, which means there should be something getting hit by the wind. But when you mention wind, it's neither force nor pressure.