Which type of conductor is used for the primary transmission of electric power: 3 phase-3 wire 3 phase-4 wire 2 phase-3 wire 2 phase-4 wire Correct answer: 1. 3 phase-3 wire Explanation: The transmission of electric power from the unit transformer (main transformer at Power plant) is termed as primary transmission. Universally the primary transmission … Read more
The flux in the transformer core relates with load: It increases with load It decreases with load Is independent of load Any of above Correct answer: 3. Is independent of load Explanation: The flux in the transformer core depends on two factors: The applied voltage The frequency of the applied voltage The change of load … Read more
Usually, a Good Voltage regulation of transformer means: VR is small VR is medium VR is high VR is infinite Correct answer: 1. VR is small Explanation: The voltage regulation of the transformer is a comparison of the output voltage at no-load and full load. The general purpose transformers are usually desired to possess a … Read more
Transformer rating is expressed in: amps kilovolt-amps (kVA) volts watts Correct answer: 2. kVA or kilovolt-amps Explanation – Why Transformer Rating is expressed in kVA The actual power factor is determined by the load. The kVA is the unit of apparent power which is defined as the product of voltage and the current flowing through … Read more
What will happen If dc supply is given to a transformer: It will provide constant DC at the output Its primary winding will burn It will not provide secondary voltage Its secondary winding will burn Correct answer: 2. Its primary winding will burn Explanation: When DC supply is given to transformer its primary winding will … Read more
Statement: The no-load current of the transformer is usually what percent of its full load value: 2 to 5% 5 to 10% 10 to 20 % 0% Correct answer: 1. 2 to 5% Explanation: The no-load current in the transformer is the current that results due to hysteresis and eddy current losses in the core. … Read more
The Power Plant which has the highest maintenance costs: Nuclear power plant Hydropower plant Diesel power plant Steam power plant Correct answer: 1. Nuclear Power Plant Explanation: A nuclear power plant requires highly skilled and qualified personnel for maintenance since the auxiliaries and all other parts are very complex in design. There a Nuclear power … Read more
Which of the following power plant has the highest efficiency: Nuclear power plant Diesel power plant Steam power plant Hydropower plant Correct answer: 4. Hydropower plant Explanation: The Hydropower Plant is the power plant with the Highest Efficiency. A hydropower plant has lowest losses during the conversion processes. The turbine is located next to the … Read more
Which one of the following has a minimum running cost: Nuclear power plant Hydropower plant Diesel power plant Steam power plant Correct answer: 2. Hydropower plant Explanation: A hydropower plant has an almost negligible running cost. Since the fuel is water which has practically NIL cost. More MCQs on Electricity Generation: Most reliable power source … Read more
Which of the following power plants is least reliable: Coal Hydro Wind Nuclear Correct answer: 3. Wind Explanation: While nuclear power plant is the most certain source for power generation. A wind farm is the least reliable source for generating power The wind fluctuations can be a serious problem resulting in reduced efficiency of turbines. … Read more