Physics · 2021
JEE Main · 18 March 2021, Shift 2 · Q18
The time taken for the magnetic energy to reach 25 % of its maximum value, when a solenoid of resistance R, inductance L is connected to a battery,…
The time taken for the magnetic energy to reach $\displaystyle 25 \%$ of its maximum value, when a solenoid of resistance R , inductance L is connected to a battery, is :
Official answer
(1)
$\displaystyle \frac{\mathrm{L}}{\mathrm{R}} \ln 2$
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JEE Main 2021 Physics question, with the answer from NTA’s final answer key. Where our answers come from.