Three point charges are located at the vertices of an equilateral triangle of side
PHYSICS · Multi-part · CBSE · Physics · Electrostatic Potential and Capacitance · Electrostatic Potential and Capacitance
Problem
Three point charges are located at the vertices of an equilateral triangle of side d. Charges at vertices P and Q are +q and +2q, respectively, while the charge at vertex R is −q. An external agent assembles the charges sequentially, bringing them in from infinity.
Assume q=1.5μC and d=0.25m.
(a) Identify which portion of the assembly process (bringing in which specific charge) requires the greatest amount of positive work from the external agent. Justify your choice qualitatively.
(b) Calculate the net work required to bring in the second charge, given that one positive charge has already been fixed at P.
(c) Determine the net work required to bring in the third charge, after the first two are in place.
(d) Compute the total electric potential energy of the final three–charge configuration and interpret its sign in terms of the stability of the arrangement.