Explain the factors affecting the value of g .

Explanation

The value of the acceleration due to gravity , g , changes from place to place on the earth . It also varies with the altitude and depth below the earth ' s surface . The factors affecting the value of g are the shape of the earth , altitude and depth below the earth ' s surface .
( 1 ) The earth is not perfectly spherical . It is somewhat flat at the poles and bulging at the equator . At the surface of the earth , the value of g is maximum `(9.832 m//s^(2))` at the poles as the polar radius is minimum , while it is minimum `( 9.78 m//s^(2))` at the equator as the equatorial radius is maximum .
( 2 ) As the height ( h ) above the earth ' s surface increases , the value of g decreases . It varies as `(1)/((R+h)^(2))`, where R is radius of the earth . ( 3 ) In the interior of the earth , on the average , the value of g is less than that at the earth ' s surface . As the depth below the earth ' s surface increases , the value of g decreases and finally it becomes zero at the centre of the earth .