Infinitely far away from a mass-->gravitational potential is zero.
As get closer-->becomes negative.
At surface-->it is the smallest value of r, i.e. the radius of the mass, hence the most negative value for gravitational potential.
But as you go below surface of Earth (say Earth is the mass, and the only mass), what happens to the value of gravitational potential as you go below surface of the Earth?
The Attempt at a Solution
I thought that, as the mass decreases by a cubic factor (volume), but the radius decreases by a linear factor, then the gravitational potential would increase (become more positive) by a factor to the power of 2, reaching zero at centre of earth?
Is this right?