1 mb Above 99.9% Ideal gas law P=PRT ATMOSPHERIC PRESSURE 5mb Example: Above 99% 10mb-- T=15C=288K p=1.2 kg/m3 t-25 mb R=[287.05JK1kg1l A so mb 豆专 [1J=INm 10 Above 9o% p=1.013x105N/m2 Abore 50% =1013mb A敢,Evee 010030 500 70090 Pressure mb) Atmospheric pressure decreases rapidly with height. Climbing to an altitude of only 5.5 km, where the pressure is 500 mb, would put you above one-half of the atmosphere's moleculesATMOSPHERIC PRESSURE Atmospheric pressure decreases rapidly with height. Climbing to an altitude of only 5.5 km, where the pressure is 500 mb, would put you above one-half of the atmosphere's molecules. Example: T= 15C = 288 K r = 1.2 kg /m3 R = [287.05 J K-1 kg-1 ] [1 J = 1 N m]  p = 1.013 x 105 N/m2 = 1013 mb Ideal Gas Law p =r R T