an inductor coil ,a capacitor and an AC source of rms voltage 24 v are in series .when frequency of the source is varied ,a maximum rms current of 6A is observed .if this inductor coil is connected to a battery of emf 12V and internal resistance 4ohms what will be the current?

 in this problem, maximum current is given i.e. it is d case of resonating frequency. we know at dis frequency X_C=X_L.  Therefore, impedence will be---

 Z=root over (R²)

   =R

   =V_rms / I_rms

  =24/6

  = 4ohm

 so. total resistance of d circuit =R+r

                                                        = 4+4 =8 ohm

  again voltage of d battery is 12 V, so current (I)= 12/8 A

                                                                                     =1.5 A

 i think d ans is correct...............rate me ifu find it correct...............