1. For a star connected three phase AC circuit o Phase voltage is equal to line...

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1. For a star connected three phase AC circuit o Phase voltage is equal to line voltage and phase current is three times the line current O Phase voltage is square root three times line voltage and phase current is equal to line current o Phase voltage is equal to line voltage and line current is equal to phase current o None of the above 2. In a three phase, delta connection O line current is equal to phase current o Line voltage is equal to phase voltage None of the above O o Line voltage and line current is zero 3. In a three phase AC circuit, the sum of all three generated voltages is O Infinite O Zero o One O None of the above 4. In a three phase AC circuit, power is measured using a Wattmeter. o True o False 5. While conducting short-circuit test on a transformer the following side is short circuited o High voltage side o Low voltage side o Primary side o Secondary side 6. The purpose of providing an iron core in a transformer is to O Provide support to windings O Reduce hysteresis loss O Decrease the reluctance of the magnetic path o Reduce eddy current losses 7. Which of the following does not change in a transformer? O Current o Voltage O Frequency O All of the above 8. When a 400 Hz transformer is operated at 50 Hz, its kVA rating is o Reduced to 1/8 o O O Increased 8 times. Unaffected Determined by load on secondary 1. For a star connected three phase AC circuit o Phase voltage is equal to line voltage and phase current is three times the line current O Phase voltage is square root three times line voltage and phase current is equal to line current o Phase voltage is equal to line voltage and line current is equal to phase current o None of the above 2. In a three phase, delta connection O line current is equal to phase current o Line voltage is equal to phase voltage None of the above O o Line voltage and line current is zero 3. In a three phase AC circuit, the sum of all three generated voltages is O Infinite O Zero o One O None of the above 4. In a three phase AC circuit, power is measured using a Wattmeter. o True o False 5. While conducting short-circuit test on a transformer the following side is short circuited o High voltage side o Low voltage side o Primary side o Secondary side 6. The purpose of providing an iron core in a transformer is to O Provide support to windings O Reduce hysteresis loss O Decrease the reluctance of the magnetic path o Reduce eddy current losses 7. Which of the following does not change in a transformer? O Current o Voltage O Frequency O All of the above 8. When a 400 Hz transformer is operated at 50 Hz, its kVA rating is o Reduced to 1/8 o O O Increased 8 times. Unaffected Determined by load on secondary

Answer rating: 100% (QA)

Answer 1 Phase voltage is equal to line voltage and phase current is three times the line current 2 None of the above 3 Zero 4 True 5 Low voltage side ... View the full answer