Easy INTEGER +4 / -1 PYQ · JEE Mains 2020

In a fluorescent lamp choke (a small transformer) 100 V of reverse voltage is produced when the choke current changes uniformly from 0.25 A to 0 in a duration of 0.025 ms. The self-inductance of the choke (in mH) is estimated to be ________.

Answer (integer) 10

Solution

V = $\left| {L{{di} \over {dt}}} \right|$ <br><br>$\Rightarrow$ L = ${V \over {\left| {{{di} \over {dt}}} \right|}}$ = ${{100} \over {{{0.25} \over {0.025 \times {{10}^{ - 3}}}}}}$ = 10 mH

About this question

Subject: Physics · Chapter: Electromagnetic Induction · Topic: Self and Mutual Inductance

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