Question
A large number of identical point masses m are placed along x-axis, at x= 0,1,2,4.........The magnitude of gravitational force on mass at origin (x=0), will be
Joshi sir comment
The magnitude of gravitational force on mass at origin (x=0), will be
Gmm/12 + Gmm/22 + Gmm/42 + Gmm/82 + .........................
= [Gmm/12][1+(1/4)+(1/16)+....................]
= Gmm[1/(1-(1/4)]
solve?