Skip to content
Login Register

#charged surface

2 public questions tagged with this topic.

Continuous Charge Distribution

What causes the electric field to be discontinuous across a charged surface, such as a thin sheet?

**Line charge concept** extends point charge to infinite wire where symmetry dictates radial field proportional to λ and inversely proportional to distance r. λ = q/L for uniform case, field direction depends on sign of λ, outward for positive. The surface charge density on the sheet generates a field that changes abruptly. Gauss’s law shows the field on either side is sigma/2ε₀ , with opposite directions, resulting in a discontinuity equal to sigma/ε₀ across the surface. Substituting values gives Surface charge density, which matches expected magnitude for this electrostatic configuration, confirming Coulomb's and Gauss's principles and charge quantization consistency.

Ref: NCERT > Physics Book > Electric Charges and Fields > Continuous Charge Distribution

View Details
Superposition Principle and Equilibrium of Charges

Why does the electric field near a charged surface exhibit a sharp increase in strength compared to regions further away

**Superposition principle** asserts net Coulomb force on charge equals vector sum of forces from each other charge independently, F_net = Σ F_i, where F_i = k q q_i/r_i² r̂_i. In equilateral triangle or square symmetry, components may cancel at centroid, producing equilibrium. The inverse-square law governs the field from charges on the surface. Near the surface, the distance r is small, making 1/r² large, resulting in a strong field that weakens rapidly as distance increases. Substituting values gives Inverse-square law, which matches expected magnitude for this electrostatic configuration, confirming Coulomb's and Gauss's principles and charge quantization consistency.

Ref: NCERT > Physics Book > Electric Charges and Fields > Superposition Principle and Equilibrium of Charges

View Details