Category Archives: Electrical Machines MCQ

This set of Electrical Machines Multiple Choice Questions & Answers (MCQs) focuses on “Autotransformers”. 1. While comparing potential transformer to an auto transformer, a potential transformer transfers power ________ a) conductively b) inductively c) both conductively as well as inductively d) electromagnetic induction 2. The statements which support the points that auto transformers are advantageous? … Read more

This set of Electrical Machines Multiple Choice Questions & Answers (MCQs) focuses on “Three Phase Transformers”. 1. A V-V connected transformer can be connected in parallel to delta-delta connected transformer but not to ___________ a) delta-star b) star-delta c) star-V d) all of the mentioned 2. Three units of single phase transformers and one single … Read more

This set of Electrical Machines Multiple Choice Questions & Answers (MCQs) focuses on “Transformer as a Magnetically Coupled Circuit”. 1. In power transformers, it is found that the iron or core losses practically varies very less, this is because ____________ a) constant core flux b) constant leakage flux c) constant leakage and core flux d) … Read more

This set of Electrical Machines Problems focuses on “Parallel Operation of Single Phase Transformers”. 1. A 2000/1000/500 three winding transformer is to be used as auto transformer with supply of 3000 V. Two loads of 1050 kVA at 3500V, and other one at 180 kVA at 1000V. The circuit representing the mentioned application is? a) … Read more

This set of Electrical Machines Multiple Choice Questions & Answers (MCQs) focuses on “Transformer Losses and Efficiency”. 1. Which of the statements made here are correct regarding the transformer? I. Maximum voltage regulation occurs at the leading p.f. II. Maximum voltage regulation occurs when load p.f. angle and impedance angle of the leakage impedance are … Read more

This set of Electrical Machines Multiple Choice Questions & Answers (MCQs) focuses on “Voltage Regulation of Transformer”. 1. A 10 kVA, 400/200 V, 1-phase transformer with 2% resistance and 2% leakage reactance. It draws steady short circuit current at which angle? a) 45° b) 75° c) 135° d) 0° 2. While conducting open circuit test … Read more

This set of Electrical Machines Multiple Choice Questions & Answers (MCQs) focuses on “Open Circuit and Short Circuit Test”. 1. Power required during the open circuit and short circuit test is? a) losses incurring in the transformer b) executing the power requirements by measuring instruments c) power for the core losses only d) all of … Read more

This set of Electrical Machines Multiple Choice Questions & Answers (MCQs) focuses on “EMF Induced in Transformer”. 1. If the transformer is excited with square wave voltage source then the shape of induced EMF will be __ a) Sinusoidal Wave b) Square Wave c) Triangular Wave d) Impulse Wave 2. If a transformer is excited … Read more

This set of Electrical Machines Assessment Questions and Answers focuses on “Equivalent Circuit of Transformer”. 1. In a transformer if the frequency of the supply is varied then the magnetizing current in the core also varies. a) True b) False 2. CRGO Laminations in a transformer are used to minimize __________ a) eddy current loss … Read more

This set of Electrical Machines Multiple Choice Questions & Answers (MCQs) focuses on “Transformer Phasor Diagram”. 1. The output voltage seen at the CRO connected at the secondary terminals is square wave. Then the flux density used for energizing the primary is? a) triangular b) sinusoidal c) saw tooth wave d) square wave 2. The … Read more