Question

In the context of conductors in electrostatic equilibrium, the relationship between electric field and the conductor's surface is:

• A. Electric field is parallel to the surface
• B. Electric field is perpendicular to the surface
• C. Electric field is tangential to the surface
• D. Electric field is zero on the surface

Hint:

Remember that electric field lines point from higher potential to lower potential and are always perpendicular to equipotential lines/surfaces. Since a conductor's surface is an equipotential, the E-field lines must emerge from it at a right angle.

Answer 1

The Correct Option is B

Step 1: Recall conductor properties in electrostatic equilibrium. A key property is constant electric potential throughout the conductor, including its surface, making the surface an equipotential.
Step 2: Relate electric field lines and equipotential surfaces. Electric field lines are always perpendicular to equipotential surfaces. A parallel (tangential) component of the electric field would exert a force causing surface charge movement.
Step 3: Apply electrostatic equilibrium. "Electrostatic equilibrium" signifies stationary charges. For charges to be stationary, there must be no net force parallel to the surface, meaning the tangential electric field component must be zero.
Step 4: Conclude the relationship. A zero tangential electric field component means the electric field vector at the surface is entirely perpendicular. The field is not zero on the surface unless the conductor is uncharged.