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Equipotential surfaces
Intermediate
Surfaces of constant potential are perpendicular to field lines.
Surfaces on which V is constant. They are perpendicular to field lines, and no work is done moving a charge along them. A conductor's surface is an equipotential.
Topographic contours are like gravitational equipotentials.
Closer spacing means a stronger field.
In more detail
Equipotential surfaces are surfaces where the electric potential is constant. Field lines are always perpendicular to equipotential surfaces, and no work is done moving along them.
Real-world uses
- Mapping electric potentials in biology and electrochemistry.
- Designing electrodes with specific equipotential shapes.
- Scientists map equipotential lines on a sheet of conductive paper to find the field around electrodes.
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Frequently asked questions
Why is no work done along an equipotential?
Because the potential does not change, so the potential energy is constant.
Can equipotentials cross?
No, because the potential would have two values at the crossing.
Why are equipotentials perpendicular to field lines?
Moving along an equipotential needs no work, so the field must be at right angles to it.
Related topics in Electrostatics
Electrostatic shielding · Electric potential · Potential difference · Relation of E and V · Electron volt · Potential energy of charges