Why Does an Inductor Store Energy After No Current?

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SUMMARY

The discussion centers on the behavior of inductors in electrical circuits, specifically addressing the misconception that an inductor can store energy after the current has ceased. The calculations presented indicate energy values for different ranges of E, but the moderator clarifies that the energy stored in an inductor is directly tied to the instantaneous current. When the current is zero, the energy stored in the inductor is also zero, confirming that an inductor does not retain energy without current flow.

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fight_club_alum
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Screen Shot 2019-11-05 at 5.45.47 AM.jpg

I calculated all the required in this problem correctly but can't understand why the sum of energy extracted and absorbed is not zero.
They are:
>0: 0J
0 <=E<=25: 4t^2 J
25 <= E <= 50: 4t^2 - 0.4t + 10 * 10^-3t J
E > 50: 0 J

Does that mean that an inductor stores energy even after there is no current?
Thanks

[Moderator's note: Moved from a technical forum and thus no template.]
 
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fight_club_alum said:
25 <= E <= 50: 4t^2 - 0.4t + 10 * 10^-3t J
Check your working.

The energy stored in an inductor depends only on the present instantaneous value of its current. So when current = 0, no energy is stored.
 
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