Physics
Physics
Problem
An isolated parallel-plate capacitor with air gap has capacitance , charge and potential difference . A conducting slab of thickness is inserted centrally between the plates so that it remains parallel to them and does not touch either plate. After insertion, the new potential difference between the plates is a) b) c) d)Intuitive explanation
When a conductor slides into a capacitor, the key insight is that the electric field inside the conductor must be zero—charges redistribute until they cancel any external field. This effectively reduces the gap where the field actually exists. Since the capacitor is isolated, the charge stays constant, so you need to find how the new effective gap changes the voltage using .
Intuitive explanation
When a conductor slides into a capacitor, the key insight is that the electric field inside the conductor must be zero—charges redistribute until they cancel any external field. This effectively reduces the gap where the field actually exists. Since the capacitor is isolated, the charge stays constant, so you need to find how the new effective gap changes the voltage using .