Mass density of a solid sphere is ρ. Radius of the sphere is R. The gravitational field at distance r from the centre of the sphere inside it is
4ρGπr3
4ρGr23
4ρGR33r2
ρGR3πr
E(r)=GMR3r for r≤R=GR3(43πR3.ρr)=4Grπρ3
The density inside a solid sphere of radius a is given by ρ =ρ0a/r where ρ0 is the density at the surface and r denotes the distance from the centre. The gravitational field due to this sphere at a distance 2a form its centre is..