A physics problem about pressure When a tornado occurs, the air pressure outside the house drops sharply to 90kpa. When the doors and windows are closed, it can be considered that the indoor air pressure is the standard atmospheric pressure, roughly taken as 100KPA. If the indoor roof area is 100 m2, how much n is the difference between the internal and external pressure on the roof, which is enough to lift the roof

A physics problem about pressure When a tornado occurs, the air pressure outside the house drops sharply to 90kpa. When the doors and windows are closed, it can be considered that the indoor air pressure is the standard atmospheric pressure, roughly taken as 100KPA. If the indoor roof area is 100 m2, how much n is the difference between the internal and external pressure on the roof, which is enough to lift the roof

f=ps
The external force is F1 = 90kpa * 100m2
The indoor force is F2 = 100KPA * 100m2
So △ f = f2-f1 = 10KPA * 100m2 = 10 * (1000N / m2) * 100m2 = 10 ＾ 6N