Visual Representation of Equipotential Surfaces

When drawing $\vec E$ arrows from equipotential voltage lines,

• $\vec E$ is $\perp$ to surface
• $\vec E$ points to lower voltage (“downhill”)
• The closer the equipotential lines are to one another, the greater the magnitude of $\vec E$

Properties of Conductors in Equilibrium

1. All excess charge is evenly distributed on the surface
2. The surface is an equipotential
3. $E=0$ inside
4. The interior is all at the same potential
5. Exterior electric field $E\perp$ the surface
6. Surface charge density and electric field strength are greatest at sharp corners