Physics Homework Help?

Question

Three equal point charges, each with charge 1.95 uC, are placed at the vertices of an equilateral triangle whose sides are of length 0.250 m.  What is the electric potential energy U of the system? (Take as zero the potential energy of the three charges when they are infinitely far apart.)

Answer 1

Three equal point charges, each with charge is .

Point charges are placed at the vertices of an equilateral triangle with side length is .

The potential energy between two charges is , where is the coulombs law constant .

Since it is an equalateral triangle, three point charges are placed at equal distances.

The total potential energy of the system is .

Substitute , and .

.

The total potential energy of the system is .