Work required to get current going

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The discussion centers on the work required against back electromotive force (emf) in a steady current scenario. It highlights that when the current is steady, the work done against back emf (Wm) is zero, yet the magnetic field (B) remains non-zero. This raises a question about the apparent inconsistency between Wm being zero and the presence of a magnetic field. The conversation suggests that transitioning from zero current to steady current necessitates a changing current, which stores energy in Wm. Ultimately, once the current stabilizes, no additional work is needed to maintain the magnetic field.
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Image from Griffith, ED, 4th ed

Wm is the work needed against the back emf. If the current is steady (meaning not changing w.r.t. time) then there is no back emf. Hence, Wm = 0. But, B due to steady current is not 0. So, R.H.S is not zero. Could anyone please resolve this inconsistency?
 
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to get that state of steady current from 0 current at some point you had to have changing current so that energy is now stored in the wm but of course now that is steady no addition wm is being stored.
 
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