500 kva, 11,000/2300 volts 60Hz transformer has 5.45% impedance and 1.2% resistance. What is the percent regulation at full load 80% power factor lagging?"     A. 3.26     B. 6.23     C. 4.21     D. 5.28

Consider the three single-phase two-winding transformers shown in Figure. 3. The high-voltage windings are connected in Y. (a) For the low-voltage side, connect the windings in A, and label the terminals a, b, and c in accordance with the American standard. (b) Relabel the terminals a', b', and c' such that VAN is 90° out of phase with V₂'b' for positive sequence. DI H₂ Figure. 3: Three-Winding Transformer

3. A non-ideal 1-phase transformer has turns ratio 5:1 with 120Vac primary.  The primary impedance is 1 + j1 Ohms, and the secondary impedance is 0.2 + j0.2 Ohms.  Assume the core impedance (R0 and X0) can be neglected.  A resistive load of 12 Ohms is connected to the secondary.   What is the primary current magnitude? What is the secondary voltage magnitude? What is the efficiency of this transformer with this load?

a single-phase transformer serves a 7.2kw resistive loadlocated 200 ft from the transformer. each conductor from the transformer to load has an impedence of (0.78+j0.052) ohms per 1000ft. if the voltage at the load terminal is 240v, the magnitude of the voltage (v)  at the transformer secondary is most nearly: