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Question
You are given a 2 µF parallel plate capacitor. How would you establish an instantaneous displacement current of 1 mA in the space between its plates?
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Solution
The capacitance of capacitor C = 2 µF
Displacement current Id = 1 mA
Charge in capacitor, q = CV
Iddt = CdV .....[∵ q = it]
or Id = `C (dV)/(dt)`
`1 xx 10^-3 = 2 xx 10^-6 xx (dV)/(dt)`
or `(dV)/(dt) = 1/2 xx 10^3` = 500 V/s
Hence by applying a varying potential difference of 500 V/s, we would produce a displacement current of the desired value.
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