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Question
Suppose the initial charge on the capacitor is 6 mC. What is the total energy stored in the circuit initially? What is the total energy at later time?
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Solution
Capacitance of the capacitor, C = 30 μF = 30 × 10−6 F
Inductance of the inductor, L = 27 mH = 27 × 10−3 H
Charge on the capacitor, Q = 6 mC = 6 × 10−3 C
Total energy stored in the capacitor can be calculated by the relation,
`"E" = 1/2 "Q"^2/"C"`
= `1/2 xx (6 xx 10^-3)^2/(30 xx 10^-6)`
= `6/10`
= 0.6 J
Total energy at a later time will remain the same because energy is shared between the capacitor and the inductor.
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