A current of 2A is passing through an inductor of 2mH. Energy stored by it is:
Correct answer: D. 4 mJ
- A. 8 mJ
- B. 10 mJ
- C. 6 mJ
- D. 4 mJ
Explanation
The energy stored in an inductor is calculated using the formula E = 1/2 (L) (I2). Given the current I = 2A and inductance L = 2mH = 2 x 10-3 H, the calculation is as follows: E = 1/2 (2 x 10-3) (2)2 = 1/2 (2 x 10−3 ) (4) = 4 x 10−3 J = 4 mJ. Therefore, the correct answer is 4 mJ. Other options result from miscalculations or incorrect application of the formula.
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