Three particles, each having a charge of 10 µC are placed at corners of an equilateral triangle of side 10 cm. The electrostatic potential energy of system is ? ( Given 1/4πεo = 9 X 109 N-m2C2) (MHT-CET ~ 2011)

Three particles, each having a charge of 10 µC are placed at corners of an equilateral triangle of side 10 cm. The electrostatic potential energy of system is ? ( Given   = 9 X 10⁹ N-m²C²) (MHT-CET ~ 2011)

a ] zero                                 b] Infinity                            c] 27 J                    d] 100 J

solution :

Electric Potential Energy :

The electric potential energy of system of system of point charges can be define as the work required to assemble the system of charges by bringing them from infinite distance to their present location.

U =(1/ 4 π ε _o ) { [ ( q ₁ q ₂  ) / r _{1 2} ] + [ ( q ₁ q ₃ ) /  r _{1 3} ] + [ ( q ₂ q ₃ ) / r _{2 3} ] }

 U = 3 (1/ 4 π ε _o )  [ (4q ² )  / a ]

U = 3 X 9 X 10 ⁹ X 10 ^{– 9}

U = 3 X 9

U = 27

The potential energy of system is given by U = 27 J

The correct option is : option [ C ]