A parallel plate capacitor having plates 6.0 cm apart is connected across the terminals of a 12.0 V battery. (a) Being as quantitative as you can, describe the location and shape of the equipotential surface that is at a potential of +6.0 V relative to the potential of the negative plate. Avoid the edges of the plates. (b) DO the same for the equipotential surface that is at +2.0 V relative to the negative plate (c) what is the potential gradient between the plates?

Question

A parallel plate capacitor having plates 6.0 cm apart is connected across the terminals of a 12.0 V battery. (a) Being as quantitative as you can, describe the location and shape of the equipotential surface that is at a potential of +6.0 V relative to the potential of the negative plate.  Avoid the edges of the plates. (b) DO the same for the equipotential surface that is at +2.0 V relative to the negative plate (c) what is the potential gradient between the plates?

ok..wouldn't the equipotential surface just be perpendicular to the electric field? or am I totally wrong?

bobpursley · Answer

If you call the negative terminal zero potential, the other terminal will be at +12. THus the six volt potential will be half the distance. The potential is a plane, ignoring edges. THe potential gradient? 12/.06 volts/meter.
The equitpotental surface is indeed perpendicular to the E field.