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Question
A capacitor has been charged by a dc source. What are the magnitude of conduction and displacement current, when it is fully charged?
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Solution
Elecric flux through plates of capacitor, `φ_E = q/ε_o`.
Here, q = constant, the capacitor is fully charged.
Displacement current , `I_D= ε_o (dφ_E)/dt = ε_od((q/ε_o)/dt) = 0 `
Contduction current, `I = c (dv)/dt = 0` as volatage becomes constant
when the capacitor becomes fully charged.
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