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Nilanjan Bhowmick AIR 3, CSIR NET (Earth Science)
Mayank vedwal Vedwal
shape of earth is geoid . Geoid is not a perfect sphere. Geoid is a shape that the ocean surface would take under the influence of the gravity of Earth. Shape of earth is not perfect because there are so many basins and hills are present on earth surface some places have positive elevation and some places have negetive elevation that's why the surface of earth is not perfect sphere.
also rotation and revolution affects the size
yes due to rotation of earth's shape distorted... due to rotation of earth equatorial distance is greater than the polar distance. But rotation of earth explain the reason of being ellipsoid in shape not the geoid shape.