V=V0(1−e−RCt)
50=100(1−e−RCt)
t=0.69×10−4sec.
JEE Main 2021 — Physics Electromagnetism

A capacitor of capacitance C=1μF is suddenly connected to a battery of 100V through a resistance R=100Ω. The time taken for the capacitor to be charged to get 50V is:
(Take ln2=0.69)
Held on 27 Jul 2021 · Verified 6 Jul 2026.
1.44×10−4s
3.33×10−4s
0.69×10−4s
0.30×10−4s
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