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Grade 11Electromagnetic Induction

How many time constants will elapse before the charge on a capacitor falls to 0.1% of its maximum value in a discharging RC circuit?

Profile image of Simran Bhatia
12 Years agoGrade 11
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1 Answer

Profile image of Aditi Chauhan
12 Years ago
Sol. q = Qe^–t/RC q = 0.1 % Q RC ⇒ Time constant = 1 * 10^–3 Q So, 1 * 10^–3 Q = Q * e^–t/RC ⇒ e^–t/RC = ln 10^–3 ⇒ t/RC = –(–6.9) = 6.9