78500km
On the surface
The distance from the surface of the Earth to its center is approximately 6,371 kilometers.
The distance between the surface at the center of a reflective surface and its focal point is equal to half the radius of curvature of the surface.
On the surface
The average distance from Earth's surface at the equator its center is about 6378 km. The distance from near the north and south poles to the center is somewhat less.
There is no fixed distance of the ozone from surface. It is said to be an approximate of 15 to 55 km.
The distance from surface to surface through the center of a planet would be that planet's "diameter".
The term that indicates the distance between the surface at the center of a reflective surface and the focal point is called the "focal length." In optics, this distance is crucial for determining how light converges or diverges when it strikes the reflective surface. The focal length is a key parameter in the design of lenses and mirrors.
No. The circumference is the distance around a circle or equaltor wheras the radius is the distance from the centre of a sphere (the centre of the earch if you will) to the surface. the diameter is twice the distance of the radius and is the distance from the surface of a sphere, through the middle point across to the other surface.
working distance
7,000 km
I assume you mean, of the gravitational field? The gravitational field is inversely proportional to the square of the distance. At a distance of 1 Earth radius, the distance from the center of the Earth is twice the distance at the Earth's surface; thus, the field strength is 1/4 what it is on the surface. If at the surface the field strength is about 9.8 meters per second square, divide that by 4 to get the field strength at a distance of one Earth radius from the surface.I assume you mean, of the gravitational field? The gravitational field is inversely proportional to the square of the distance. At a distance of 1 Earth radius, the distance from the center of the Earth is twice the distance at the Earth's surface; thus, the field strength is 1/4 what it is on the surface. If at the surface the field strength is about 9.8 meters per second square, divide that by 4 to get the field strength at a distance of one Earth radius from the surface.I assume you mean, of the gravitational field? The gravitational field is inversely proportional to the square of the distance. At a distance of 1 Earth radius, the distance from the center of the Earth is twice the distance at the Earth's surface; thus, the field strength is 1/4 what it is on the surface. If at the surface the field strength is about 9.8 meters per second square, divide that by 4 to get the field strength at a distance of one Earth radius from the surface.I assume you mean, of the gravitational field? The gravitational field is inversely proportional to the square of the distance. At a distance of 1 Earth radius, the distance from the center of the Earth is twice the distance at the Earth's surface; thus, the field strength is 1/4 what it is on the surface. If at the surface the field strength is about 9.8 meters per second square, divide that by 4 to get the field strength at a distance of one Earth radius from the surface.