For discharging of an RC circuit, V=V0e−t/τ So, when V=2V0 2V0=V0e−t/τ ln21=−τt⇒τ=ln2t From graph when V=2V0,t=100 s∴τ=ln2100=144.3 sec
JEE Main 2012 — Physics Electromagnetism
The figure shows an experimental plot for discharging of a capacitor in an R−C circuit. The time constant τ of this circuit lies between: 
Held on 30 Apr 2012 · Verified 6 Jul 2026.
150 sec and 200 sec
0 and 50 sec
50 sec and 100 sec
100 sec and 150 sec
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