Question:
When a current changes at the rate of $30\ \text{A s}^{-1}$, the induced emf is $12\ \text{V}$. The self-inductance of the coil is:
When a current changes at the rate of $30\ \text{A s}^{-1}$, the induced emf is $12\ \text{V}$. The self-inductance of the coil is:
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$L = \text{emf} / (\text{rate of change of current})$.
Updated On: Apr 28, 2026
- 0.4 H
- 0.2 H
- 0.6 H
- 0.3 H
- 0.1 H
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The Correct Option is A
Solution and Explanation
Step 1: Concept
Induced emf $\epsilon = L \frac{di}{dt}$.
Step 2: Analysis
Given $\epsilon = 12\ V$ and $\frac{di}{dt} = 30\ As^{-1}$.
Step 3: Calculation
$12 = L(30) \implies L = 12/30 = 0.4\ H$. Final Answer: (A)
Induced emf $\epsilon = L \frac{di}{dt}$.
Step 2: Analysis
Given $\epsilon = 12\ V$ and $\frac{di}{dt} = 30\ As^{-1}$.
Step 3: Calculation
$12 = L(30) \implies L = 12/30 = 0.4\ H$. Final Answer: (A)
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