Question

Four point charges are positioned on the rim of a circle. The charge on each of the four is +0.5 µC, +1.5 µC, -1.0 µC, and -0.5 µC. If the electrical potential at the center of the circle due to the +0.5 µC charge alone is 4.5 104 V, what is the total electric potential at the center due to the four charges?

Answer 1

Electric potential is a scalar, so the position of the charges on the circle wont matter, just the distance from the center to the charges.

Find each potential from each charge, then add them to the one given.

Vgiven=kq/r=k/r (.5)
4.5E4=k/r (.5 so k/r= 9.0E4

Total potential
V=4.5E4 + (9.0E4)(q2+q3+q4)
check my thinking.