Question

The density of atmospheric air is about 1.15 kg/m³, which we assume is constant. How large an absolute pressure will a pilot see when flying 1500 m above ground level where the pressure is 101 kPa. 

Answer 1

Assume g and ρ are constant then the pressure difference to carry a column of height 1500 m

∆P = ρgh = 1.15 kg/m³ × 9.807 ms^-2 × 1500 m

= 16 917 Pa = 16.9 kPa 

The pressure on top of the column of air is then

P = P₀ – ∆P = 101 – 16.9 = 84.1 kPa