Question

What is the approximate distance from the surface of the earth to its center?
A. 4,000 miles
B. 1,000 miles
C. 40,000 miles
D. 10,000 miles

Answer 1

Hint: The distance between the surface of the earth and its center can only be given approximately as the earth is not a perfect sphere, it is actually an oblate spheroid. The distance to the center of the earth from the equator is 6,378 km or 33,963 miles, whereas the distance to the center of the earth from a pole is 6,357km or 3,950 miles.

Complete answer: The average distance from the surface of the earth to its center is 6,371 km or 3,959 miles. Because of the oblate spheroid shape of the earth there is a difference of 21km from the distance of the center from the equator to the distance of the center from a pole. The radius of the earth is 6,731km approximately, where the crust is 35km (21 mile) thick; the mantle is 2855 km (1774 miles) thick and at the deepest point there is the Kola Superdeep Borehole, which is just 12 km deep.
Therefore, from the above discussion it can be said that all the figures related to the distance of the center of the earth with its surface comes near about 4,000 miles.

Hence, option A, is the correct option.

Note: As the interior of the earth is extremely hot and under high pressure, no other layer could be discovered beneath the core. Therefore, the estimation of the distance of the center of the earth with its surface is calculated accordingly with the discovery of humankind.