A Question

Three points, A, B, and C, are shown in the vicinity of a positive charge. Which takes more work, to move a negative charge from point A to point C or from point B to point C?

  1. Moving the charge from A to C takes more work
  2. Moving the charge from B to C takes more work
  3. Neither, the work required is equal in both cases

Points A and B are on the same equipotential, so it takes no work at all to move a charge from A to B. C is on a different equipotential, and work is involved in moving the charge between the equipotentials. The negative charge is attracted to the positive charge, so we have to do positive work to move the charge to C, further away from the positive charge.