Capacitors - continued.

Let’s see what happens if you charge the system.

To energize (charge) the system, the switch is closed. This causes the upper plate (A) to become positively charged and the lower plate (B) to become negatively charged.

The charged plates A and B create an electric field (similar to a magnetic field) which occupies the region between the two plates.

The electric field pierces through the dielectric placed between the two plates.

The electric field causes the atoms and molecules to re-orient themselves. Their negative side is turned toward the upper plate and the positive side turns toward the lower plate. This causes the positive charge in plate A and negative charge in plate B to be held captive by the dielectric. At this time, if you were to open the switch, the capacitor will stay charged.

To discharge the capacitor, use a wire to connect the Plate A with the Plate B. This cause a temporary surge of current which will subside almost immediately.