Four small point charges (each of equal magnitude q) are placed at four corners of a regular tetrahedron of side a. find out potential energy of charge system

Explanation

Potential energy of system :
`U = U_(12) + U_(13) + U_(14) + U_(23) + U_(24) + U_(34)`
`U = (-kq^(2))/(a) + (kq^(2))/(a) + (-kq^(2))/(a) + (-kq^(2))/(a) + (kq^(2))/(a) + (-kq^(2))/(a)`
Total potential energy of this charge system
`U = (-2kq^(2))/(a)`