An isolation transformer has primary to secondary turns ratio of: 1:1 1:2 2:1 Any of above Correct answer: 1. 1:1
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In Electrical Machines the hysteresis effect results in
ElectricIn Electrical Machines the hysteresis effect results in: Power loss Reduction of efficiency Raising temperature of machine All of above Correct answer: 4. All of above
The capacitor start, capacitor run induction motor acts as a true 2-phase motor at which of the following condition
ElectricThe capacitor start, capacitor run induction motor acts as a true 2-phase motor at which of the following condition: No load All load Full load Starting Correct answer: 3. Full load
A DC series motor will over speed for which of the following condition
ElectricA DC series motor will over speed for which of the following condition: When field is opened When load is increased When armature circuit opened When load is removed Correct answer: 4. When load is removed
The flux in the core of single-phase transformer is
ElectricThe flux in core of single phase transformer is: Purely rotating one Purely alternating one Partly alternating and partly rotating None of above Correct answer: 2. Purely alternating one
Certain transformer has full-load copper losses of 500 W. What is the value of the copper loss at half load
ElectricCertain transformer has full-load copper losses of 500 W. What is value of copper loss at half load: 62.5 W 125 W 250 W 750 W Correct answer: 2. 125 W Solution: Copper losses vary with the square of current. ...
What is the full load primary current of a 3000/150 V, 30 kVA transformer
ElectricWhat is the full load primary current of a 3000/150 V, 30 kVA transformer: 2 A 5 A 10 A 20 A Correct answer: 10 A Solution: I = kVA/Primary voltage = 30 kVA/3000 = 30 * 1000 / 3000 ...
The overall efficiency of a DC generator is maximum when its variable loss equals
ElectricThe overall efficiency of a DC generator is maximum when its variable loss equals: Stray losses Iron losses Constant losses Mechanical losses Correct answer: 3. Constant losses
Transformer MCQ Part 9
ElectricTransformer MCQ Questions The iron core in transformer provides _____________ path to main flux The iron core in transformer provides _____________ path to main flux: Low reluctance High reluctance High conductivity Low resistance Correct answer: 1. Low reluctance The core ...
Transformer MCQ Part 8
ElectricTransformer MCQ Questions The efficiency of two identical transformers under load conditions can be determined by which of the following tests The efficiency of two identical transformers under load conditions can be determined by which of the following tests: Back ...