While deriving the expression for the capacitance of a parallel-plate capacitor
PHYSICS · Multi-part · AP · Physics 2: Algebra-based · Electric Force Field and Potential · Electric Force Field and Potential
Problem
While deriving the expression for the capacitance of a parallel-plate capacitor, certain idealisations are introduced regarding the electric field between the plates.
(a) List any two principal assumptions made about the distribution of charge and the nature of the electric field inside the region enclosed by the plates.
(b) Give a reason why the effect of the plate edges is neglected in this derivation. How does this simplification influence the calculation of the potential difference?
(c) Explain qualitatively how the assumption of uniform surface charge density on each plate leads to the conclusion that the electric field between the plates is uniform.