JEE Mains · Physics · STD 12 -6. Electromagnetic induction
A \(12\,V\) battery connected to a coil of resistance \(6 \,\Omega\) through a switch, drives a constant current in the circuit. The switch is opened in \(1\,ms\). The emf induced across the coil is \(20 \;V\). The inductance of the coil is ........... \(mH\)
- A \(5\)
- B \(12\)
- C \(8\)
- D \(10\)
Answer & Solution
Correct Answer
(D) \(10\)
Step-by-step Solution
Detailed explanation
Induced emf \(=- L \frac{ dI }{ dt }\) \(\Rightarrow 20=- L \frac{(0-2)}{10^{-3}}\) \(\Rightarrow L =10\,mH\)
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