A building has a flat roof of area 42.0 m2. Wind blows over the top of the roof at 14.8 m/s. The air inside the building is stationary. What is the TOTAL force acting on the roof?

Answer 1

Using Bernoulli's Theorem

(P1- P2) / Density = 1/2 ( v2²- V1²), No change in GPE

Force / Area = 1/2 ( 14.8)² * density of air , Pressure = Force /Area ,

Force =1/2 ( 42.0 ) (14.8) ² *1.22

Force = 133.6 N

(I have used density of air = 1.22)