JEE Mains · Physics · STD 12 -Electromagnetic induction
- JEE Mains 2021
- Hard
- MCQ
The current \((i)\) at time \(t =0\) and \(t =\infty\) respectively for the given circuit is

Pick an option to check your answer.
Answer & Solution
Correct Answer
(D) \(\frac{5 E }{18}, \frac{10 E }{33}\)
Step-by-step Solution
Detailed explanation
At \(t=0,\) current through inductor is zero,
hence \(R _{ eq }=(5+1) \|(5+4)=\frac{18}{5}\)
\(i _{1}=\frac{ E }{18 / 5}=\frac{5 E }{18}\)
At \(t=\infty\), inductor becomes a simple wire and now the circuit will be as shown in figure
hence \(R _{ eq }=(5 \| 5)+(4 \| 1)=\frac{33}{10} ; \quad(\| \Rightarrow\) parallel \()\)
\(i _{2}=\frac{ E }{33 / 10}=\frac{10 E }{33}\)
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