Work required to get current going

[Pushoam]

Image from Griffith, ED, 4th ed

W_m 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, W_m = 0. But, B due to steady current is not 0. So, R.H.S is not zero. Could anyone please resolve this inconsistency?

 

[timetraveller123]

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.