Three particles, each of mass m, are placed at the vertices of an equilateral triangle of side a. The gravitational field intensity at the cenrtroid of the triangle is then
r=AO=BO=CO=l√3
EA=Gmr2
=3Gml2 along OA
EB=3GMl
EC=3Gml
They are co planer and equal in magnitude and make an angle of 120∘
The resultant field is zero.