Electrostatics: One of the job interview question:
Plate capacitor, with area of electrodes S, and distance between them d,has air as dielectric. Capacitor is connected to constant voltage source. Then, it is disconnected and dielectric is introduced between plates with relative permitivity Ɛr>1,
What happens to current between plates? does current drops (asuming to zero if there is no voltage), increases, or stays the same?