Four parallel-plate capacitors—labeled I, II, III

PHYSICS · Multi-part · CBSE · Physics · Electrostatic Potential and Capacitance · Electrostatic Potential and Capacitance

Problem

Four parallel-plate capacitors—labeled I, II, III, and IV—each consist of two square metal plates connected to identical charge sources so that the magnitude of charge on every plate is the same positive value QQ. The physical characteristics of the four capacitors are given below. • Capacitor I: plate area A=0.020 m2A=0.020\,\text{m}^2, separation d=1.0 mmd=1.0\,\text{mm}, dielectric constant κ=1.0\kappa=1.0 • Capacitor II: plate area A=0.020 m2A=0.020\,\text{m}^2, separation d=0.50 mmd=0.50\,\text{mm}, dielectric constant κ=2.0\kappa=2.0 • Capacitor III: plate area A=0.010 m2A=0.010\,\text{m}^2, separation d=1.0 mmd=1.0\,\text{mm}, dielectric constant κ=4.0\kappa=4.0 • Capacitor IV: plate area A=0.040 m2A=0.040\,\text{m}^2, separation d=2.0 mmd=2.0\,\text{mm}, dielectric constant κ=1.0\kappa=1.0 Throughout this problem, ignore edge effects and assume the electric field is uniform between the plates of each capacitor. (a) Rank the magnitudes of the uniform electric fields inside capacitors I–IV from largest to smallest. If any fields are equal, state that explicitly. (b) Provide a qualitative explanation for your ranking. In your discussion, refer to how each physical parameter (AA, dd, and κ\kappa) influences the electric field when the stored charge QQ is the same.

Related theory

Browse the problem library