A current of 5A is flowing through a 0.5 H inductor. If the current starts increasing at a rate of 2 A/S, power consumption by the inductor will be

(1)Induced emf ε=L  didt=0.5  ×  2  volt=1 voltand  thus  emf  opposes  the  growth of current.∴   power consumed by  the  inductor  =  1  ×  5  W=5  watt.