Potential energy of a 

system of charges 

 

1) Potential energy of a system of two point charges:

1) Suppose there is a charge q1 with position vecto

2) Now a new charge q2 is bring closour to a position with position vector 

3) Now is the distance between the point charges  q1 and q2.

4) then electrostatic potential at q2 due to charge q1 is



5) the potential energy on charge
q2 is

Potential energy  = potential × charge



Or



This the potential energy of the system of two charges.

 

2) Potential energy of a system of three point charges:


1) Suppose there are three point charges q1, q2, & q3, and their position vectors

r1, r2, & r3 respectively.


2) Then potential energy of the system is



 3) Potential energy of a system of four point charges:


1) Suppose there have four charges q1, q2, q3 & q4 with their position vectors

r1, r2, r3 & r4.


2) then the potential energy of the system is