the lesson of electric machines and drivers -- transformer questions question: the data of a single phase transformer are as following; nominal primary voltage U1n= 230V nominal secondary voltage U2m= 12V line frequency f= 50 Hz apparent power S=50 VA loading resistor on secondary side is RL=3ohm strayed field self induction coefficient in the simplified equivalent circuit Ls=Ls1+Ls2=0.06 H ? winding ratio of transformer N1/N2 ? nominal primary current I1n? nominal secondary current I2n? primary side transformed vaue of the loading resistor R'2?