Molecules in air in the atmosphere are attracted by gravitational
force of the earth. Explain why all of them do not fall into the earth
just like an apple falling from a tree.
Dear student,
Air molecules in the atmosphere experience vertically downward force due to gravity, just like an apple falling vertically from a tree. Due to temperature, the air molecules have random motion. Due to it, the velocity of air molecules is not exactly in the vertical downward direction. the downward gravity pull on air molecules increase the density of air in the atmosphere close to earth. It is due to this reason, the density of air decrease as we go up.
Regards