Question

Electric Potential Energy of Three Point Charges 6 of 10 > Part A Three qual point charos, each with charge 125μ are placo atthe verties of an oq lateral trian le whose sides areoflongh 0400 m of the system? (Take as zero the potential energy of the three charges when they are infinitely far apart) What to elechi potential energy U use eo-8.05x10"12 NCnǐ for the permittivity of free space. 12-о N-m Hint 1. How to approach the problem Use the equation for the electric potential energy between two point charges to calculate the energy for each interaction between two of the three point charges. The sum of these energies will be the total electric potential energy. Be careful to avoid double counting. Hint 2. Find the electric potential energy of one pair Assume that one charge is interacting with a second charge, ignoring any effects from the third charge. What is the electrie potential energy Ura for this single interaction? Express your answer in joules to three significant figures. View Available Hint(s) Hint 1. Electric potential energy of a pair of charges Rocall that the electrio potont al enday U between two charges q, and g, separated by a distance r is given by the formula U12-

Answer 1

Given is:-

Charge on each point charge   

g1 = g2 = g3 = g = 1.25,iC = 1.25 × 10-6 c

each side of the equilateral triangle is = 0.400 m

Now,

The electric potential energy between the two charges is given by

Kqiq2

thus

12

similarly

hence the energy of the whole system is

or

by plugging all the values we get

and

Thus, the electric potential energy of the given system of three charges that are placed at the vertices of an equilateral triangle is 0.105 J