A. Inside a conductor the electrostatic field is zero.
B. Electric field at the surface of a charged conductor does not depend on its surface charge density.
C. The interior of a charged conductor can have no excess charge in the static situation.
D. At the surface of a charged conductor, the electrostatic field must be normal to the surface at every point.
E. The electrostatic potential is zero everywhere inside the charged conductor.
Choose the correct answer from the options given below :
A, C and D only
Evaluating Statements on Conductors in Electrostatics
We examine each statement to determine its validity in the context of electrostatics and charged conductors.
Statement A: Inside a conductor the electrostatic field is zero.
For a conductor in electrostatic equilibrium, the net electric field within its volume must be zero. If a field existed, charges would move, preventing equilibrium. This statement is correct.
Statement B: Electric field at the surface of a charged conductor does not depend on its surface charge density.
The electric field ($E$) at the surface of a conductor is given by the relationship $E = \frac{\sigma}{\epsilon_0}$, where $\sigma$ is the surface charge density and $\epsilon_0$ is the permittivity of free space. This clearly shows the field is dependent on $\sigma$. This statement is incorrect.
Statement C: The interior of a charged conductor can have no excess charge in the static situation.
In electrostatics, any net charge on a conductor resides exclusively on its outer surface. Consequently, the volume charge density inside the conductor is zero. This statement is correct.
Statement D: At the surface of a charged conductor, the electrostatic field must be normal to the surface at every point.
If there were a tangential component of the electric field at the surface, surface charges would experience a force and move, violating the condition of static equilibrium. Hence, the field must be perpendicular (normal) to the surface. This statement is correct.
Statement E: The electrostatic potential is zero everywhere inside the charged conductor.
A conductor in electrostatic equilibrium is an equipotential body, meaning the potential is constant throughout. However, this constant potential is not necessarily zero; it depends on the charge distribution and reference points. It is zero only under specific conditions, like being grounded. This statement is incorrect.
Summary of Correct Statements
Based on the analysis, statements A, C, and D are correct.
Thus, the correct option is A, C and D only.
Similar Questions
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