In addition, the internal structure of the earth: the outer silicate solid shell, the highly viscous asthenosphere and the mantle, the liquid outer core and the solid inner core which are much more viscous than the mantle. The deep underground is full of fiery magma, and the downward pressure is greater, so it is impossible to dig to the opposite side.
Extended data:
The causes of the formation of the earth's gravity
If the earth's surface is completely covered by free-flowing liquid water, then the surface of this liquid water presents a flat sphere, which is slightly flat at the poles and expands at the equator, which has been briefly described in the previous section. This ideal shape, called a sphere, will be perfectly balanced with all gravity and rotating forces. Newton's law is the basis of gravity.
As we all know, the basic expression of this law is that the gravitational force between two particles, m 1 and m2, is directly proportional to the product of their masses and inversely proportional to the square of the center distance between the two particles. If f here is the force acting on m2, then R 1 is the unit vector of m 1 to m2, and r is the distance of m 1 to m2. Adding a negative sign means that efforts are mutually attractive.
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