Four charges, each of value q, are placed at the four corners of a square of side a. What is the potential at the centre of the square

Four charges, each of value q, are placed at the four corners of a squ

1.	Four charges, each of value q, are placed at the four corners of a square of side a. What is the potential at the centre of the square
Answer» Solution : Consider four masses each of MASS m at the corners of a square of side l,We have four mass pairs at DISTANCE l and two diagonal pairs at distance`sqrt(2)`l hence, W(R)= - 4 `(Gm^(2))/(l) - 2 (Gm^(2))/(sqrt(2)l)` = - `(2.Gm^(2))/(l ) (2 + (1)/(sqrt(2))) = - 5.41 (Gm^(2))/(l)` The gravtational potential at the centre of the square `(r = sqrt(2)l//2)` is U(r)= - `4 sqrt(2) (Gm)/(l)` .