while reading up on the Hall Effect, i realised that you could set up a distribution of space charge and hold them with the magnetic field, while cutting the wire connecting the metal plate to the external battery(to prevent charge form entering or leaving the plate). hence producing a capacitor.
But i realised that if you did so then there would be no drift velocity and hence no force on the charges due to the magnetic field. End result no capacitor.But then brownian motion came to the rescue, untill i realised that the net velocity is 0. any other way? (no heating of the metal plate allowed(work function thing)