# Electric Field Question

by BlueCardBird
Tags: electric field, electric field lines
 P: 887 Electric Field Question Do you know calculus? Your equation seems to be another way of writing $|E| = \Delta V/\Delta r$, which is only an approximation. The correct value is gotten by taking the limit as Delta goes to 0. Then you get: $E=-\nabla V$ In the special case of infinite parallel plate, they give the same answer, but for a curved E field you get a more accurate answer for smaller step size.