Q. Atmospheric pressure exerted on earth is due to the which of the following reasons? Answer:
Gravitational pull
Notes: The atmospheric pressure at the surface of the Earth is due to gravitational pull of the earth and is about 14.7 psi. That means that the weight of a column of air which has a cross section of 1 square inch and which stretches from the surface of the Earth to space is 14.7 pounds.