{"knowledge_schema": {"broad_category": "Physics \u2192 Electrostatics \u2192 Conductors and Electric Fields", "refinement": "This problem involves understanding the behavior of electric fields and potentials in conductors, particularly when they are grounded and contain charges.", "specific_scope": "The focus is on a spherical conductor with a cavity containing a charge, and determining the electric potential at a point outside the conductor when it is grounded.", "goal": "Identify the electric potential at a point outside the conductor, given the conditions of grounding and the presence of a charge within the cavity."}, "summary": "In this problem, we analyze a grounded spherical conductor with a charge placed in a cavity. When the conductor is grounded, it allows charges to move freely, neutralizing the effect of the charge inside the cavity on the external electric field. As a result, the potential at any point outside the conductor becomes zero volts. This illustrates the principle that a grounded conductor shields external points from internal charges."}