Show that, in an ideal transformer, the input electrical power is equal to the output electrical power. [5 marks]
2. Corrected_text: If the phase voltage in a star-connected 3-phase system is 240 V, determine the line voltage. (ii) If the phase current in a delta-connected 3-phase system is 12 A, determine the line current. [5 marks]
3. Corrected_text: For a given application, a three-phase induction machine is to be run as a motor at a rotor speed of Nr = 550 rpm using a 50 Hz 3-phase voltage source. An 8-pole machine, a 10-pole machine, and a 12-pole machine are available. Which one would you choose, and why? (Hint: first determine at what fractional slip each of the machines would operate). [5 marks]