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In an LCR circuit as shown below both switches are open initially. Now switch S 1 is closed S 2 kept open. (q is charge on the capacitor and τ = RC is Capacitive time constant). Which of the following statement is correct ? S 1 S 2 L C V R

1. At t = 2 τ , q = CV (1 – e –2 )
2. At t = 2 τ , q = CV (1 – e –1 )
3. Work done by the battery is half of the energy dissipated in the resistor
4. At t = τ , q = CV/2

Correct answer: At t = 2 τ , q = CV (1 – e –2 )

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