The atmosphere is held to the earth by (a) gravity (b) wind (c) clouds (d) earth’s magnetic field
(a) gravity The universal law of gravitation states that every particle attracts every other particle in the universe with a force that is directly proportional to the product of the masses and inversely proportional to the square of the distance between them. The universal law of gravitation gives the gravitational force between any two bodies having some mass. For two objects of masses, m1 and m2 and the distance between them r, the force (F) of attraction acting between them is given by the universal law of gravitation as: Where G is the universal gravitation constant having the value 6.673 x 10-11 N m2/kg2 and it is independent of mass and radius of the earth. Due to gravity, the earth pulls all objects towards it. The air that surrounds our planet is held in place by gravity, and this envelope of air is referred to as the atmosphere.
