Determine the average force of the wind on the building

[Fisicks]

Homework Statement

Air in a 140 km/h wind strikes head-on the face of a building 60 m wide by 50 m high and is brought to rest. If air has a mass of 1.3 kg per cubic meter, determine the average force of the wind on the building.

Homework Equations

The book seems to suggest the impulse equation.

The Attempt at a Solution

I have stared at the problem for a while. I thought I could use the impulse equation but I don't have a change in time. Also, it gives you the density which is in 3 dimensions and you only know two from the problem, length and height of the building. Overall, I'm just stumped which is weird for me.

 

[tiny-tim]

Hi Fisicks!

… I thought I could use the impulse equation but I don't have a change in time. Also, it gives you the density which is in 3 dimensions and you only know two from the problem, length and height of the building.

Hint: what is the volume of air stopped in one second?

 

[Fisicks]

thanks!