`implies` In `g(r) = 4/3 pi Grrho, 4/3 piGrho` Gp is constant .
`:. g(r) prop r `
Means, the gravitational acceleration (g) at a point inside the earth is directly proportional to the distance of that point from the centre of the earth.
`implies` And `g(r) = (GM)/r^2` where `r gt gt R_E` so , where `g(r) prop 1/r^2` where ` r gt gt R_E`. Hence starting from the centre of the earth g(r) increases in directly proportion as r increases and then outside the surface g(r) decreases as inverse square of distance.
`implies` The variations in gravitational acceleration with below the surface of earth and above the height from the surface is shown as in figure.
