All Free Electrical Engineering MCQs with Answers

• A. Exhaust fan
• B. Lathe machine
• C. Welding transformer
• D. All of the above

Explanation: A welding transformer produces a fluctuating load because the welding arc is repeatedly struck, interrupted, and varied during operation.

• A. peak load plant
• B. base load plant
• C. stand-by plant
• D. spinning reserve plant
• E. any of the above

Explanation: Nuclear stations are designed for continuous operation because their fuel and operating characteristics favour steady generation rather…

• A. sinking fund depreciation
• B. straight line depreciation
• C. reducing balances depreciation
• D. none of the above

Explanation: In the sinking-fund method, interest earned on earlier deposits contributes to the required depreciation fund, so the annual deposit…

• A. fixed charges
• B. semi-fixed charges
• C. running charges
• D. all of the above

Explanation: The annual cost of operating a power plant is divided into fixed charges, semi-fixed charges, and running charges.

• A. equal to unity
• B. less than unity
• C. more than unity
• D. none of the above

Explanation: Utilization factor is the ratio of maximum demand to the plant's rated capacity.

• A. nuclear power plant
• B. hydro power plant
• C. diesel power plant
• D. both B and C
• E. none of the above

Explanation: Diesel and hydroelectric plants can be brought into service very quickly, unlike nuclear plants, which require lengthy starting and…

• A. diesel engine
• B. hydraulic turbine
• C. gas turbine
• D. steam turbine
• E. any of the above

Explanation: Generating stations may use diesel engines, hydraulic turbines, gas turbines, or steam turbines as their prime movers, depending on the…

• A. dependent upon the energy consumed
• B. dependent upon the maximum demand of the consumer
• C. both A and B
• D. neither A nor B

Explanation: In a two-part or Hopkinson tariff, the demand charge is based on the consumer's maximum demand, usually measured in kW or kVA.

• A. the capital cost divided by number of year of life
• B. the capital cost minus the salvage value, is divided by the number of years of life
• C. increasing a uniform sum of money per annum at stipulated rate of interest
• D. none of the above

Explanation: Straight-line depreciation spreads the depreciable amount uniformly over the plant life.

• A. thermal plant
• B. diesel plant
• C. hydroelectric plant
• D. none of these

Explanation: Thermal plants generally have high depreciation charges because their equipment operates at high temperatures and pressures and their…

• A. sinking fund method
• B. straight line method
• C. both A. and B.
• D. none of the above

Explanation: Both the straight-line and sinking-fund methods are used to calculate annual depreciation.

• A. load survey method
• B. statistical methods
• C. mathematical method
• D. economic parameters
• E. all of the above

Explanation: Demand can be estimated from consumer load surveys, statistical and mathematical analysis, and economic indicators.

• A. the greatest of all "short time interval averaged" demand during a period
• B. instantaneous maximum value of kVA supplied during a period
• C. both A. or B.
• D. none of the above

Explanation: Maximum demand is the highest average load recorded over a specified short interval during the period.

• A. less number of consumers
• B. more number of consumers
• C. neither A. nor B.
• D. either A. or B.

Explanation: A high diversity factor means consumers reach their individual peaks at different times, so their combined station demand is lower.

• A. Solar power plant
• B. Tidal power plant
• C. Wind power plant
• D. Any of the above

Explanation: Solar, wind, and tidal generation depend on naturally occurring conditions and cannot be dispatched freely whenever demand requires.

• A. Fuel cost
• B. Interest on capital
• C. Depreciation
• D. Insurance charges

Explanation: Fuel expense changes with the amount of energy generated, so it is a running or variable cost.

• A. nuclear power plants
• B. diesel generating plants
• C. steam power stations
• D. None

Explanation: Nuclear fuel contains very high energy per unit mass, so only a small quantity must be transported for large energy production.

• A. Fuel cost
• B. Interest on capital
• C. Insurance charges
• D. Depreciation

Explanation: Fuel cost varies with plant operation and energy generation, making it a variable cost.

• A. Nuclear power plant
• B. Hydro-electric power plants
• C. Thermal power plants
• D. Diesel engine power plants

Explanation: Thermal plants contain boilers, turbines, coal-handling systems and auxiliaries that require frequent servicing, so their maintenance cost…

• A. Maintenance cost
• B. Fuel cost
• C. Salaries of high officials
• D. Salaries of operating staff

Explanation: Fuel, operating-staff salaries and maintenance are directly associated with running a plant.