A large exhaust fan in a laboratory room keeps the pressure inside at 10 cm water relative vacuum to the hallway. What is the net force on the door measuring 1.9 m by 1.1 m?
The net force on the door is the difference between the forces on the two sides as the pressure times the area
F = Poutside A – Pinside A = ∆P × A
= 10 cm H2O × 1.9 m × 1.1 m
= 0.10 × 9.80638 kPa × 2.09 m2
= 2049 N
