AP ECET ELECTRICAL AND ELECTRONICS ENGINEERING (EEE) Multiple Choice Questions (MCQs)
AP ECET Electrical and Electronics Engineering (EEE) MCQs
Unit III: A.C. Circuits and Transformers
31. The impedance in a series R-L-C circuit is a function of:
a) Frequency
b) Voltage
c) Current
d) Power
Answer: a) Frequency
32. In a resonant R-L-C circuit, the impedance is:
a) Minimum
b) Maximum
c) Zero
d) Infinity
Answer: a) Minimum
33. In a series R-L-C circuit, resonance occurs when:
a) Inductive reactance equals capacitive reactance
b) Resistance equals inductive reactance
c) Inductive reactance equals resistance
d) Capacitive reactance equals resistance
Answer: a) Inductive reactance equals capacitive reactance
34. In a parallel R-L-C circuit, the total impedance is:
a) The sum of the individual impedances
b) The reciprocal of the sum of the reciprocals of the individual impedances
c) Equal to the sum of the resistance and reactance
d) None of the above
Answer: b) The reciprocal of the sum of the reciprocals of the individual impedances
35. The power factor in a polyphase system is defined as the ratio of:
a) Active power to total power
b) Reactive power to total power
c) Apparent power to total power
d) None of the above
Answer: a) Active power to total power
36. The two-wattmeter method is used to measure:
a) Total power in a three-phase system
b) Power in a single-phase system
c) Efficiency of a transformer
d) Voltage in a polyphase system
Answer: a) Total power in a three-phase system
37. A transformer operates on the principle of:
a) Faraday's law of electromagnetic induction
b) Lenz's law
c) Ohm’s law
d) Ampere’s law
Answer: a) Faraday's law of electromagnetic induction
38. The efficiency of a transformer is the ratio of:
a) Output power to input power
b) Input power to output power
c) Primary voltage to secondary voltage
d) None of the above
Answer: a) Output power to input power
39. In a transformer, the voltage regulation is defined as the difference between:
a) Rated voltage and no-load voltage
b) No-load voltage and full-load voltage
c) Full-load voltage and rated voltage
d) None of the above
Answer: b) No-load voltage and full-load voltage
40. The equivalent circuit of a transformer consists of:
a) Primary resistance, primary reactance, and magnetizing reactance
b) Primary voltage and secondary voltage
c) Load impedance and supply impedance
d) None of the above
Answer: a) Primary resistance, primary reactance, and magnetizing reactance
41. The efficiency of a transformer is maximum when:
a) Primary and secondary currents are equal
b) Iron losses and copper losses are equal
c) The load is half the full load
d) None of the above
Answer: b) Iron losses and copper losses are equal
42. The function of the cooling system in a transformer is to:
a) Increase the core flux
b) Maintain a constant temperature
c) Reduce the eddy current losses
d) Improve the efficiency of the transformer
Answer: b) Maintain a constant temperature
43. In a three-phase transformer, the primary and secondary windings are connected in:
a) Star and Delta combination only
b) Delta and Delta combination only
c) Star and Star combination only
d) Any combination of star or delta
Answer: d) Any combination of star or delta
44. An auto-transformer is different from a two-winding transformer because:
a) It has a single winding shared by both primary and secondary
b) It operates only on alternating current
c) It has no efficiency
d) It can only be used in low-power applications
Answer: a) It has a single winding shared by both primary and secondary
45. The main advantage of an auto-transformer over a two-winding transformer is:
a) Higher efficiency
b) Lower cost and smaller size
c) Better voltage regulation
d) None of the above
Answer: b) Lower cost and smaller size
<< Previous Page l Next Page >>
Note/Caution: studentsbizz.com does not promise a job or an interview in exchange for money. Fraudsters may ask you to pay under the pretext of a registration fee or refundable fee, but please be aware that legitimate employers will not require such payments.
Join in Our Groups
@ 2024 Students Bizz Platform. All Rights Reserved.