Question

The value of acceleration due to gravity of earth:
(A) Is maximum at the equator
(B) Is minimum at the equator
(C) Is the same at the equator and the poles
(D) Is zero at the poles

Answer 1

The main concept to answer this question lies in the fact that the shape of the Earth is oblate spheroid. Due to this reason the acceleration due to gravity that is experienced by a body is different in different places on the surface of the Earth. So the main concept is to give a detailed explanation about the shape of the Earth and then write the answer from the mentioned options.

Complete step by step answer
We should know that the value of g or acceleration due to gravity changes from place to place due to the oblate spheroid shape of that of the Earth and also the rotation of the Earth. The main reason behind this is the shape of the Earth.
Hence we can say that it is inversely proportional to that of the square of the radius. So it is least at the equator and maximum at the poles. As because the equatorial radius is 6378.2 km which is more than the polar radius which is 6356.8 km.
So we can say that acceleration due to gravity is maximum at the poles and minimum at the equator. Hence the value of acceleration due to gravity of earth is minimum at the equator.

So the correct answer is option B.

Note We should know that as the earth is of a shape which is best described as an oblate spheroid, the radius of the Earth near the equator is much more as compared to the radius of the Earth near the poles. As for a source mass, the value of g or acceleration due to gravity is always inversely proportional to the square of that of the radius of the Earth, there is a variation with the latitude because of the shape of the Earth.