Four identical point charges (+2.51 nC) are placed at the corners of a rectangle, which measures 4.00 m by 7.00 m. If the electric potential is taken to be zero at infinity, what is the potential at the geometric center of this rectangle?

Answer 1

distance of each charge to the centre of rectangle,d=sqrt(3.5^2+2^2)=4.031m A charge contribute in the potential V=9*10^9*2.51*10^-9/4.031 V=5.604v since d charge are equal and are at equal distance from centre,the electric potential at centre=4*5.604=22.42v