The acceleration due to gravity at the Earth's surface depends on

The acceleration due to gravity (g) at the Earth's surface is determined by the formula g = GM/R², where G is the universal gravitational constant, M is the mass of the Earth, and R is the radius of the Earth [5]. This derivation comes from equating Newton's Second Law (F=ma) with the Universal Law of Gravitation. Consequently, the value of 'g' is directly proportional to the Earth's mass and inversely proportional to the square of its radius. Variations in Earth's shape, such as being an oblate spheroid with a larger radius at the equator than at the poles, result in 'g' being greater at the poles and less at the equator. Additionally, local mass distribution anomalies can influence the specific value of gravity at different surface locations [2]. Therefore, both mass and radius are the fundamental physical parameters determining gravitational acceleration.

Sources

1. [5] Physical Geography by PMF IAS, Manjunath Thamminidi, PMF IAS (1st ed.) > Chapter 7: Tectonics > Gravitational Anomalies > p. 108
2. [2] Science ,Class VIII . NCERT(Revised ed 2025) > Chapter 5: Exploring Forces > A step further > p. 75