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JEE MAIN 2021
18-03-21 S2
Question
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, is :
Select the correct option:
A
$\frac{\mathrm{L}}{\mathrm{R}} \ln 5$
B
infinite
C
$\frac{\mathrm{L}}{\mathrm{R}} \ln 2$
D
$\frac{\mathrm{L}}{\mathrm{R}} \ln 10$
✓ Correct! Well done.
✗ Incorrect. Try again or view the solution.
Solution
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