ExamBro
ExamBro
JEE Mains · Physics · STD 12 -Electromagnetic induction
  • JEE Mains 2020
  • Medium
  • MCQ

An emf of \(20\; \mathrm{V}\) is applied at time \(\mathrm{t}=0\) to a circuit containing in series \(10\; \mathrm{mH}\) inductor and \(5 \;\Omega\) resistor. The ratio of the currents at time \(\mathrm{t}=\infty\) and at \(t=40\; s\) is close to : (Take \(e^{2}=7.389\) )

Pick an option to check your answer.
Verified Solution

Answer & Solution

Correct Answer

(B) \(1.15\)

Step-by-step Solution

Detailed explanation

\(\mathrm{i}=\mathrm{i}_{0}\left(1-\mathrm{e}^{-\mathrm{R}t/ \mathrm{L}}\right)\)

\(\frac{\mathrm{i}_{0}}{\mathrm{i}}=\frac{1}{1-\mathrm{e}^{-2 \times 10^{4}}}\)

\(\frac{i_{0}}{i}=1\)

 

Same subject
Explore more questions on app