Suppose that three point charges, `q_(a),q_(b) and q_(c)` are arranged at the vertices of a right-angled triangle, as shown. What is the absolute potential at the position of the third charge, if `q_(a)= -6.0 muC,q_(b) = +4.0 muC,q_(c) = +2.0 muC,a=4.0 m and b=3.0 m` ?

Explanation

The electric potential at P ( the position of the third charge) due to the presence of the first charge is .
`V_(a) = k_(e )(q_(b))/(b) = ( 9 xx 10^(9)) ( (4 xx 10^(-6)))/((3))= 1.20 xx 10^(4)V`.
The net potential of the third charge `V_(c )` is simply the algebraic sum of the potentials due to the others two charges taken is isolation. Thus,
`V_(c ) = V_(a) + V_(b) = 1.20 xx 10^(3) V`