U=21Cq2=2C1(q0e−t/T)2=2Cq02e−2t/T( where τ=CR) U=Uie−2t/τ 21Ui=Uie−2t1/τ 21=e−2t1/τ⇒t1=2Tln2 Now q=q0e−t/T 41q0=q0e−t/2 T t2=Tln4=2Tln2 ∴t2t1=41
JEE Main 2010 — Physics Electromagnetism
Let C be the capacitance of a capacitor discharging through a resistor R. Suppose t1 is the time taken for the energy stored in the capacitor to reduce to half its initial value and t2 is the time taken for the charge to reduce to one-fourth its initial value. Then the ratio t1/t2 will be
Held on 30 Apr 2010 · Verified 6 Jul 2026.
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