Question 128: Electromagnetic Induction

Question

A coil of inductance $300$ $mH$ and resistance $2\,\Omega $ is connected to a source of voltage $2$ $V$. The current reaches half of its steady state value in

Accepted Answer

KEY CONCEPT :
The charging of inductance given
by, $i = {i_0}\left( {1 - {e^{ - {{Rt} \over L}}}} ight)$
${{{i_0}} \over 2} = {i_0}\left( {1 - {e^{ - {{Rt} \over L}}}} ight) \Rightarrow {e^{ - {{Rt} \over L}}} = {1 \over 2}$
Taking log on both the sides,
$ - {{Rt} \over L} = \log 1 - \log 2$
$ \Rightarrow t = {L \over R}\log 2 = {{300 	imes {{10}^{ - 3}}} \over 2} 	imes 0.69$
$ \Rightarrow t - 0.1\,\sec .$

Answer

$0.1$ $s$

Answer

$0.05$ $s$

Answer

$0.3$ $s$

Answer

$0.15$ $s$

Electromagnetic Induction

A coil of inductance 300 mH and resistance 2\,\Omega is connected to a source of voltage 2 V. The current reaches half of its steady state value in

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