Question

What is the value of g at the center of the earth?

Answer 1

1. The value of acceleration due to gravity decreases when a body goes inside the earth's surface.
2. At the centre of Earth, the force due to the upper half of the Earth will cancel the force due to the lower half.
3. Force due to any portion of the Earth at the centre will be cancelled due to the portion opposite to it.
4. Thus, the gravitational force at the centre on anybody will be 0.
5. Since, from Newton's law, we know $F=mass\times gravity$.
6. Since the mass m of an object can never be 0. Therefore, when F = 0, g has to be 0. Thus, the value of g is zero at the centre of Earth.

Hence, the value of g at the centre of the earth is zero.