Case: Read the passage and answer the following question(s).
Two spherical cavities (A and B) of radii y and x respectively are hollowed out from the interior of a conducting sphere of radius R. Charges q1 and q2 are placed at center of cavities A and B. The situation is depicted in the figure given:

If the potential of the conductor is 1 V, what is the potential at an arbitrary point P at the distance r from the center of the cavity A (r < y) ?
Answer & explanation
Correct answer: option 4
Potential at point P = Potential of the conductor + Potential due to charge q1 at center + Potential due to induced charges at inner surface