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Question
The charge on a parallel plate capacitor varies as q = q0 cos 2πνt. The plates are very large and close together (area = A, separation = d). Neglecting the edge effects, find the displacement current through the capacitor?
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Solution
This displacement current through the capacitor is given by,
`I_d = I_c = (dq)/(dt)` ......(i)
Here we are given, q = q0 cos 2πνt
Putting this value in equation (i), we get
`I_d = I_c = - q_0 sin 2pivt xx 2 piv`
`I_d = I_c = - 2 pivq_0 sin 2pivt`
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