Method of images — UPSC Physics Optional IFoS 2025 Paper I

(i) What is the method of images ? What are the conditions which must be satisfied while applying the method of images to deal with electrostatic problems ?

(ii) A point charge \text{Q} is located at the point (\text{a}, 0, \text{b}) between two semi-infinite conducting planes intersecting at right angles as shown in the figure. Using the method of images, determine the potential at point \text{P}(\text{x}, \text{y}, \text{z}) in the region \text{z} \ge 0 and \text{x} \ge 0 and the force on \text{Q}.