q=CV(1−et/τ)
At t=2τ
q=CV(1−e−2)
JEE Main 2013 — Physics Electromagnetism
In an LCR circuit as shown below both switches are open initially. Now switch S1 is closed, S2 kept open. (q is charge on the capacitor and τ=RC is capacitive time constant). Which of the following statement is correct?

Held on 7 Apr 2013 · Verified 6 Jul 2026.
At t=2τ, q=CV (1−e−2)
At t=2τ, q=CV (1−e−1)
Work done by the battery is half of the energy dissipated in the resistor
At t=τ, q=CV/2
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