1. Gravitation: Question 3 (15)

Explain why the value of g is zero at the centre of the earth.
The value of g on the surface of the earth is given by g = \(GM\over R^2\). Thus, the value of g depends on the mass of the earth (M) and its radius (R). As we go inside the earth’s surface, the radius (R) and the mass (M) of the earth contributing towards the gravitational force goes on decreasing. Due to the combined result of this change in mass and radius, the value of g becomes zero at the centre of the earth. 2 Marks

Explain why the value of g is zero at the centre of the earth.

The value of g on the surface of the earth is given by g = \(GM\over R^2\).
Thus, the value of g depends on the mass of the earth (M) and its radius (R).
As we go inside the earth’s surface, the radius (R) and the mass (M) of the earth contributing towards the gravitational force goes on decreasing.
Due to the combined result of this change in mass and radius, the value of g becomes zero at the centre of the earth.

2 Marks