Question

One of the dangers of tornados and hurricanes is the rapid drop in air pressure that is associated with such storms. Assume that the air pressure inside of a sealed house is 1.02 atm when a hurricane hits. The hurricane rapidly decreases the external air pressure to 0.910 atm. A square window in an outside wall of the house measures 2.02 m on each side. What net force (directed outwards) is exerted on this window? (1 atm = 1.01 × 105 Pa.)

Answer 1

Answer:

     F = 8.25 10⁴ N

Explanation:

The definition of pressure is

      P = F / A

      F = P A

Let's use Newton's second law in the window

      F = F₁- F₂

      F = P₁ A - P₂  A

      F = (P₁ -P₂)  A

The area of ​​a square window is

     A = L²

     F = (P₁ -P₂) L²

Let's reduce the magnitudes to the SI system

     P₁ = 1.2 atm (1.01 10⁵ Pa / 1 atm) = 1.212 10⁵ Pa

     P₂ = 0.910 10⁵ atm = 0.9191 10⁵ Pa

Let's calculate

      F = (1.1212 - 0.9191) 10⁵ 2.02²

     F = 0.8246 10⁵ N

     F = 8.25 10⁴ N