Question

Point charges create equipotential lines that are circular around the charge (in the plane of the paper). What is the potential energy, in nJ, of a 1 nC charge located 1.99 m from a 2 nC charge ?

Answer 1

The potential energy between two charges can be written as:

`U_e=(kq_1q_2)/(r)`

In our case, it'll be equal to:

`U_e=(9*10^9*1*10^(-9)*2*10^(-9))/(1.99)=9.045nJ`

Then, our answer is PE=9.045nJ