Question

A point charge ‘q’ is kept at each of the vertices of an equilateral triangle having each side ‘a’. Total electrostatic potential energy of the system is ______.

Options

• `(1/(4 pi epsilon_0)) (3 q^2)/a^2`

• `(1/(4 pi epsilon_0)) (3 q)/a`

• `(1/(4 pi epsilon_0)) (3 q^2)/a`

• `(1/(4 pi epsilon_0)) (3 q)/a^2`

Answer 1

A point charge ‘q’ is kept at each of the vertices of an equilateral triangle having each side ‘a’. Total electrostatic potential energy of the system is `bbunderline((1/(4 pi epsilon_0)) (3 q^2)/a)`.

Explanation:

U = `1/(4 pi epsilon_0) [(q_1 q_2)/R_12 + (q_1 q_3)/r_13 + (q_2 q_3)/r_23]`

= `1/(4 pi epsilon_0) [q^2/a + q^2/a + q^2/a]`

= `1/(4 pi epsilon_0)*(3 q^2)/a`