The gravity of the earth comes from the gravity of the earth, and the objects on the surface of the earth, part of which is the gravity we perceive, and part of which acts as the centripetal force along with the rotation of the earth.
gravity is one of the inherent qualities of mass. Every object is bound to attract each other. Although the nature of gravity has yet to be determined, people have long been aware of its existence and function. Objects close to the earth, without exception, are attracted to the center of the mass of the earth. Because any object on the surface of the earth is really insignificant compared with the mass of the earth itself.
Extended data:
The value of gravity acceleration varies according to the altitude and latitude of different places. The acceleration of gravity is related to the mass of the moon. The earth's gravity is formed by adding the mass of the moon. Without the moon's gravity, it is not 9.7833, and the acceleration of gravity is also related to the mass of the moon.
the unit of gravity acceleration should also be "N.S" Newton N(kg.m/s). For example, in terms of sea level, the value of gravity acceleration at the equator of the earth is 9.7833 N.S2, and that at the North Pole is about 9.83N.S2? . Generally speaking, at the same altitude, the acceleration of gravity at the equator is the smallest, while that at the poles is the largest. )
Before 1935, the World Meteorological Organization took the acceleration of gravity g as 9.8 m/s2. After 1935, WMO took the sea level at latitude 45 as the benchmark and took g as 9.8665 m/s2. (it can be written as g45)
However, due to the progress of measurement technology, g45? The value of is no longer 9.8665 kg.m/s2. Without changing g = 9.8665 m/s2? Under the premise of, now take the gravity acceleration at sea level and latitude 45.542 as the reference value of G, which is the general M.K.S unit.
Reference: Baidu Encyclopedia of Gravity.