Physics · 2020
JEE Main · 7 January 2020, Shift 2 · Q14
An emf of 20 V is applied at time t =0 to a circuit containing in series 10 mH inductor and 5 Ω resistor. The ratio of the currents at time t =∞ and…
An emf of $\displaystyle 20$ V is applied at time $\displaystyle \mathrm{t}=0$ to a circuit containing in series $\displaystyle 10$ mH inductor and $\displaystyle 5 \Omega$ resistor. The ratio of the currents at time $\displaystyle \mathrm{t}=\infty$ and at $\displaystyle \mathrm{t}=40 \mathrm{~s}$ is close to : (Take $\displaystyle \mathrm{e}^2=7.389$ )
Official answer
(1)
$\displaystyle 1.06$
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JEE Main 2020 Physics question, with the answer from NTA’s final answer key. Where our answers come from.