A 2 H inductor carries a steady current of 3 A. How much energy is stored in its magnetic field?
Answer and explanation
Correct answer: B. 9 J, from half of L times I squared
- Step 1: Use . Step 2. J. Answer: 9 J. Why not the others: 18 J omits the half; 6 J is ; 3 J halves LI.
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