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Question
A capacitor of capacitance ‘C’ is being charged by connecting it across a dc source along with an ammeter. Will the ammeter show a momentary deflection during the process of charging? If so, how would you explain this momentary deflection and the resulting continuity of current in the circuit? Write the expression for the current inside the capacitor.
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Solution
Yes, the ammeter shows a momentary deflection during the process of charging because changing electric field produce displacement current between the plates of the capacitor.
The resulting continuity of current in the circuit is because the magnitude of electric field and charge over the area of the capacitor plates is constant.
Current inside the capacitor,
`I_D = in_0 (dphi_E)/(dt)`
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