When the current of a coil changes from 8A to 2A in 3×10^−2 s, the emf induced in the coil is 2V. The self-inductance of the coil (in mH)
Correct answer: D. 10
- A. 1
- B. 5
- C. 20
- D. 10
Explanation
D is the correct answer. The formula for induced emf (E) due to change in current in a coil is given by E=−LΔI/Δt , where L is the self-inductance of the coil, ΔI is the change in current, and Δt is the change in time. Rearranging the formula, we have L=−E⋅Δt/ΔI . Substituting the given values, we get L=-2*3×10^−2/2-8 =10 mH.
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