Let us assume the complete sphere. The upper hemisphere is denoted by 4 and the lower by B. Combined field intensity at P or Q is E =
GM
(2R)2
=
G
4R2
4
3
πR3ρ =
πGρR
3
It is obvious that intensity at P and Q will be unlike parallel. It is clear that is magnitude of intensity at Q due to only the hemisphere B is E0 then at P it will be