Free Power Systems MCQs with Answers

• A. Cost of wages
• B. Cost of fuel
• C. Cost of lubricants
• D. All of the above

Explanation: Running cost is incurred during operation, including wages for operating staff, fuel consumption, and lubricants.

• A. kW
• B. kWh
• C. kVAR
• D. none of the above

Explanation: A capacitor supplies reactive power, so its rating is expressed in kilovolt-amperes reactive, or kVAR.

• A. Nuclear
• B. Hydro
• C. Thermal
• D. Diesel

Explanation: A hydroelectric station has no fuel cost and comparatively low operating and maintenance expenses after construction.

• A. Peak load plant
• B. Base load plant
• C. Nuclear power plant
• D. Hydro electric plant

Explanation: A peak-load plant operates only when demand is high, so its average load remains below its maximum demand and its load factor cannot reach…

• A. fixed charges
• B. operating or running charges
• C. both A. and (b)
• D. either A. or (b)

Explanation: In a two-part tariff, fixed charges depend mainly on maximum demand, whereas running charges depend on energy consumed.

• A. Load survey method
• B. Mathematical method
• C. Statistical method
• D. Economic parameters

Explanation: Statistical methods estimate demand from previous consumption patterns, diversity, growth and seasonal variation.

• A. Nuclear power plant
• B. Hydro power plant
• C. Steam power plant
• D. Diesel power plant

Explanation: Steam plants generally have the lowest overall efficiency among these conventional options because several heat-conversion and mechanical…

• A. thermodynamic cycle
• B. Rankin cycle
• C. Vapor pressure cycle
• D. Carton cycle

Explanation: Steam power stations operate on the Rankine cycle, in which water is pumped, heated into steam, expanded through a turbine, and then…

• A. Thermal Power Plant
• B. Hydro Power Plant
• C. Nuclear Power Plant
• D. Diesel Power Plant

Explanation: Hydro plants produce electricity without burning fuel, so they have very low direct air pollution during operation.

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

Explanation: Thermal plants usually require high maintenance because boilers, turbines, condensers, fuel-handling equipment, and pollution-control…

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

Explanation: Overall efficiency equals thermal efficiency multiplied by the efficiencies of the boiler, turbine, generator, and other auxiliaries.

• A. 6.6 kV
• B. 9.9 kV
• C. 11kV
• D. 13.2kV

Explanation: Generating voltages such as 6.6 kV, 11 kV, and 13.2 kV are commonly used in alternators.

• A. Carnot cycle
• B. Rankin cycle
• C. Brayton cycle
• D. Dual cycle

Explanation: A gas turbine works on the Brayton cycle: air is compressed, heat is added during combustion, and the hot gases expand through the…

• A. high
• B. low
• C. remain same
• D. depend on the plan type

Explanation: A high diversity factor means the station's maximum coincident demand is much lower than the sum of individual maximum demands.

• A. unity
• B. zero
• C. negative.
• D. infinity.

Explanation: Load factor is average load divided by maximum demand. Its ideal maximum is unity, meaning the plant operates at its maximum demand…

• A. monograph.
• B. load graph.
• C. discharge graph.
• D. hydro graph

Explanation: The discharge plotted against time is called a hydrograph, which shows how the water flow available to the plant varies over time.

• A. radium
• B. cadmium
• C. uranium
• D. all of the above

Explanation: Uranium is the commonly used nuclear reactor fuel because its nuclei can undergo a controlled fission chain reaction.

• A. average load/maximum load.
• B. maximum demand/connected load
• C. connected load/maximum demand.
• D. average load x maximum load

Explanation: Demand factor compares the maximum demand with the total connected load: demand factor = maximum demand / connected load.

• A. super heater
• B. condenser
• C. economizer
• D. chimney

Explanation: The economizer recovers heat from flue gases to preheat the boiler feedwater, improving plant efficiency and reducing fuel consumption.

• A. nuclear power plants
• B. diesel generating plants
• C. thermal power plants
• D. steam power stations

Explanation: Nuclear fuel has very high energy density, so only a small quantity is needed and its transportation requirement is least among the listed…