Question

The atmospheric pressure is due to the:
A. Sky above our head
B. Air mass surrounding earth
C. Gravitational force of sun and other planets
D. Mass of the earth

Answer 1

For solving this question, first we need to know what atmospheric pressure is. Also, there are some parameters which cause this pressure which we need to know, too.

Complete answer:
-To begin with, it is important to know that the air in the environment has weight, and it presses against every single thing it touches. This pressure is known as atmospheric pressure which is defined as the force exerted on the surface by the air above it due to the gravitational force of the earth. Moreover, atmospheric pressure is generally determined by the hydrostatic pressure caused by the air weight which is above the measurement point.
-Now if we see the main cause of atmospheric pressure, it is the gravitational attraction of the planet on the atmospheric gases above the surface. Also, it is a function of some parameters such as the mass of the earth, the radius of the surface and the composition and amount of the gases and their distribution in the atmosphere vertically.Thus, from these factors, we can say that one of the reasons is mass of the earth which causes the atmospheric pressure.

Hence, option D is the right choice.

Note: Atmospheric pressure decreases with increase in altitude. Also, the amount of oxygen available to breathe also decreases with decrease in atmospheric pressure. That is why people can become sick or even die when atmospheric pressure becomes very low causing insufficient amounts of oxygen to breathe.