This paper critically examines the widely taught claim that the electric field inside a charged sphere is zero, arguing that its unqualified presentation constitutes a pedagogical oversimplification. Using Gauss’s Law as a unifying framework, the study systematically compares conducting and insulating spheres, both solid and hollow, emphasizing the essential roles of charge mobility, symmetry, and material properties. By integrating insights from Physics Education Research and advanced theoretical concepts such as the Uniqueness Theorem and charge relaxation time, the paper exposes the roots of persistent student misconceptions. An assumption-centered instructional protocol is proposed to replace rote memorization with conceptually robust reasoning in electrostatics education.
Mahir et al. (Thu,) studied this question.