(a) Draw the 'exact' equivalent circuit of a transformer, labelling and giving a short description of the function of each model component. 

(b) Initially, assuming an ideal transformer, calculate the magnitude and phase of the load voltage and load current with respect to the supply voltage when a load of (5 + j4)Ω is supplied from a single-phase 120V, 50Hz supply through the ideal transformer with a turns ratio, primary to secondary, of 3:1. 

(c) Calculate the actual phase and amplitude of the load current, the power supplied to the load and the operating efficiency of the transformer, given that in practice, the transformer has a primary winding resistance and leakage reactance of 0.5Ω  and 1Ω  respectively, the transformer secondary has a resistance of 0.1Ω  and a leakage reactance of 0.15Ω , and the transformer core losses are 12W. (Use the appropriate approximate' equivalent circuit in your calculations). 

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