These are sample MCQs to indicate pattern, may or may not appear in examination G.M. VEDAK INSTITUTE OF TECHNOLOGY Program: Mechanical Engineering Curriculum Scheme: Revised 2016 Examination: Final Year Semester VIII Course Code:MEDLO8041 and Course Name: PPE Time: 1 hour Max. Marks: 50 Q is defined as A Object oriented design always dominates the structural design A Maximum demand X Connected load A Maximum demand/ Connected laod A Connected laod/Maximum demand Q is defined as A Average load/Maximum demand A Average load X Maximum demand A Maximum demand/Average laod A Maximum demand X Connected load Q is always A Equal to unity A More than unity A More than than twenty A Less than unity Q Load factor for heavy industries may be taken as A 10 to 15% A 15 to 40% A 50 to 70% A 70 to 80% Q Which of the following is not suitable to use as peak plant? A Hydroelectric power plant A Gas power plant A Diesel elected plant A plant Q Which of the following power plant cannot be used as plant? A Diesel power plant A Hydroelectric power plant A A Thermal power plant The system supplying base and peak loads will be more economical if power is supplied by ______Q A Only gas turbine power plant A Only thermal power plant A Only Diesel power plant A Combined operation of various power plants Q Load factor of is generally A Less then unity A Equal to unity A More than unity A More than Ten Q Diversity factor is defined as A Sum of individual maximum demands/Maximum demand of entire group A Maximum demand of entire group/Sum of individual maximum demands A Maximum demand of entire group X Sum of individual maximum demands A Maximum demand of entire group + Sum of individual maximum demands Q In order to have lower cost of electrical energy generation A The load factor and diversity factor should be low. A The load factor should be low but diversity factor should be high A The load factor should be low but diversity factor low. A The load factor and diversity factors should be high. Q A load curve is a plot of A Load versus generation capacity A Load versus current A Load versus time A Load versus cost of power Q The area under the load curve represents ______A Maximum demand A The average load on power system A Number of units generated A Load factor Q Load duration curve indicates ______A The variation of load during different hours of the day A Total number of units generated for the given demand A Total energy consumed by the load A The number of hours for which the particular load lasts during a day Q Which of the following is called as cold reserve? A Reserve capacity available but not ready for use A Reserve capacity available and ready for use A Generating capacity connected to bus and ready to take load A Capacity in service in excess of peak load Q Which of the following has highest diversity factor? A Commercial lightning A Domestic lightning A Industrial power A Domestic power Q In a power plant if the maximum demand on plant is equal to the plant capacity then A Diversity factor will be unity A Plant reserve capacity will be zero A Load factor will be unity A Load factor will be zero Q Which of the following have highest operating cost? A Solar plant A Hydroelectric power plant A Thermal power plant A Nuclear power plant Q Which of the following least affect the cost of electricity produced in thermal power plant? A Cost of fuel A The load factor A Cost of transportation A Salaries of higher officials Q The control rods in the control system of nuclear reactors are used to A Absorb excess neutrons A Control fuel consumption A Control temperature A Control the pressure Which of the following type of pump is used in liquid metal cooled reactor for circulation of liquid Q metal A Centrifugal A Axial A Reciprocation A Electromagnetic Q Each fission of U₂₃₅ produces on the average ______fast neutrons as a product of reaction A 2.46 A 24.6 A 246 A 2460 Q The coolant used in boiling water reactor is A CO2 A Pressurised water A Mixture of water and steam A Liquid metal Q Effective moderators are those materials which contain A Light weight atoms A Heavy weight atoms A Critical atoms A Zero weight atoms A nuclear fission is initiated when the critical energy as compared to neutron binding energy of the Q atoms is A Same A More A Less A There is no such criterion Q The commonly used material for shielding is A Lead or concrete A Lead and tin A Graphite or cadmium A Thick galvanized sheets Q Enriched uranium is one in which A Percentage of U₂₃₅ has been artificially increased A Percentage of U has been artificially increased A Percentage of U₂₃₄ has been artificially increased A Extra energy is pumped from outside Q Gas cooled reactor uses following materials as moderator, and coolant A Graphite, CO2 A Graphite, air A Heavy water, CO2 A Lead, H2 Q Pick up the wrong statement fast breeder reactors A Operate at extremely high power densities A Are liquid metal cooled A Produce more fuel than they consume A Use water as coolant Enriched uranium is required as a fuel in a nuclear reactor, when light water is used as moderator and Q coolant, because light water has A High neutron absorption cross-section A Low moderating efficiency A High neutron scatter cross-section A Low neutron absorption cross-section Q Electron volt is the unit of A Atomic power A Energy A Voltage A Radio activity Q A moderator, in nuclear power plants, is a medium introduced into the fuel mass in order to A Slow down the speed of fast moving neutrons A Give faster speed to fast moving neutrons A Reduce the temperature A Extracts heat from nuclear reaction Q One gram of uranium will produce energy equivalent to approximately A 1 tonne of high grade A 4.5 tonnes of high grade coal A 10 tonnes of high grade coal A 100 tonnes of high grade coal Where reactor operation is designed with fast neutrons such as in reactors using highly enriched fuel, Q the moderator used is A Heavy water A Graphite A Carbon dioxide A No moderator is needed Q The nuclear energy is measured as A MeV A Curie A Farads A MW Q Isotopes of same elements have A Same atomic number and different masses A Same chemical properties but different atomic numbers A Different masses and different atomic numbers A Different chemical properties and same atomic numbers Q A boiling water reactor uses following as fuel A Enriched uranium A Plutonium A Thorium A Uranium Q Maximum supplementary firing means ______A Minimum fuel that can be fired A Maximum fuel that can fired with the oxygen available in turbine A Maximum fuel that can be fired in given time A Maximum fuel that can be fired at given pressure Q By using combined cycle steam and gas power plant ______A Specific fuel consumption can be decreased A Efficiency increased A Specific fuel consumption can be decreased and efficiency increased A Specific fuel consumption can be decreased and efficiency decreased Gas and Steam turbine combined power plant produces more electricity than traditional power plants Q by how much percent? A 25 A 40 A 50 A The given statement is false Q Marine compound power plants are also the combined gas and steam power plants A Statement is true A Stetement is false A Statement is incomplete A Statement is inappropriate Q How many sections does waste heat recovery boiler have in steam generators? A 1 A 2 A 3 A 4 Q Turbines that are run by exhaust gases are called ______A Power recovery turbines A Stepped turbines A Turbo compounded engine A Turbo stepped turbines Q What are turbo-compound engines? A Turbines run at exhausts of Otto and diesel cycles A Combination of turbofan and turbojet engines A Combination of turboprop and turbofan engines A Combination of turboprop and turbojet engines Q The installation time for a gas turbine power plant is ______A Comparatively less than thermal power plant A Comparatively more than thermal power plant A Equal to thermal power plant A Very much longer than thermal power plant Q Heating value of coal is approximately A 1000-2000 kcal / kg A 2000-4000 kcal / kg A 5000-6500 kcal / kg A 9000-10,500 kcal / kg Q What is the function of cyclon separator in pneumatich ash handling system A To separate the lighter dust particles A To force up the movement of ash in pipes and tubes A To draw out the dust from furnace A To separate minute coal particles Q Coal used in power plant is also known as A Steam coal A Charcoal A Coke A Soft coal Q Which of the following is considered as superior quality of coal ? A Bituminous coal A peat A lignite A coke Q In a power plant, coal is carried from storage place to boilers generally by means of A Bucket A V-belts A trolleys A Manually Q Live storage of coal in a power plant means A Coal ready for combustion A Preheated coal A Storage of coal sufficient to meet 24 hour demand of the plant A Coal in transit. What would be the most important factor under consideration for the site selection of a thermal Q plant? A Availabilty of fuel A Availability of water A Distance from the populated area A cost and the type of land Q Pulverized coal is A Coal free from ash A Non-smoking coal A Coal which bums For long time A Coal broken into fine particles Q Equipment used for pulverizing the coal is known as A Ball mill A Hopper A burner A stoker Q Power plants using coal work closely on known which of the following cycle ? A Otto cycle A Binary vapor cycle A Brayton cycle A Q What does ESP stand for in dust collection? A Endothermic sensor plate A Extrasensory perception A Electrostatic precipitators A Electronic stability program Q In thermal power plants, coal is transferred from bunker to the other places by A Belt conveyor A Bucket conveyor A Fork lift truck A Overhead crane The correct sequence of factors in order of deceasing importance for location of a thermal power Q plant is A Load, coal, water A Coal, water, load A Water, coal, load A water, load, coal Q Coal fired power plant boilers manufactured in India generally use: A Pulverized coal combustion A Oil burners A Bas burners A Chain grate stoker In a pulverised-fuel-fired large power boiler, then heat transfer from the burning fuel to the walls of Q the furnace is A By conduction only A By convection only A By conduction and convection A Predominantly by radiation Q which of these is not a Circuit of Steam Power Plant A Condenser and Fan circuit A Coal and Ash Circuit A Feed water and Steam Circuit A Air and Gas Circuit Q What can not be used to change over existing oil power plant into coal fired plant A Coal-Diesel Mixture A Coal-Oil Mixture A Coal-Water Mixture A Coal-Methanol Mixture Q Which method is used to handle Pulverized Fuel A Central or Bin system A Hand feed mechanism A Foot operated Feeders A Gravity Feeders Q Water hammer developes in A Draft tube A Penstock A Turbine A Surge tank Q Hydrology is the science which deals with A River water A Rain water A Surface and underground water A Sea water Q The flow-mass curve is graphical representation of A Cumulative discharge and time A Discharge and percentage probability of flow being equaled or exceeded A Cumulative discharge, volume and time in chronological order A Discharge and time in chronological order Q What do you call a graph which is plotted for discharge versus time? A Fluid graph A Rain graph A Flow graph A Hydro graph Q For an impulse turbine which of the following statements is correct A It makes use of a draft tube A It is not exposed to atmosphere A It is most suited for low head installation A It operates with complete conversion of pressure head to velocity head Q In reaction turbine the function of a draft tube is to A Provide safety to turbine A Prevent air from entering A Reconvert the kinetic energy to flow energy A Increase the rate of flow Q Surge tank is used to A Prevent occurrence of hydraulic jump A Smoothen the flow A Relieve pipeline of excessive pressure transients A Avoid reversal of flow Q Pelton turbines are mostly A Horizontal A Vertical A Inclined A Overhead Q The annual depreciation of a hydropower plant is about A 0.5% to 1.5% A 10% to 15% A 15% to 20% A 20% t0 25% Q Operating charges are minimum in the case of______for same power output A Gas turbine power plant A Hydel plant A Thermal plant A Nuclear palnt Q Francis turbine is ususlly used for A High heads A Medium heads A Low heads A Any type of head Q Pelton turbine is suitable for high head and A High Discharge A Low discharge A Medium discharge A Quick discharge Q In high head hydel plant the velocity of water in penstock is about A 1m/s A 4m/s A 7m/s A 12m/s Q Running cost of a hydroelectric power plant is A Equal to running cost of a steam power plant A Less than running cost of a steam power plant A More than running cost of a steam power plant A Double the running cost of a steam power plant Q Location of surge tank in a hydro-electric station is near to the A Tailrace A Turbine A Reservoir A Draft tube Q Pelton wheel is used for minimum of the following heads A 40m A 120m A 180m and above A 10m Q Which of the following surge tank is also called a throlled surge tank? A Inclined surge tank A Expansion chamber surge tank A Restricted orifice surge tank A Open type surge tank Q Gross head of a hydropower station is A Difference of water level between the level in storage and tail race A Height of water level in the river where storage is provided A Height of water level in the river where tail race is provided A Height of water level from surge tank and tail race is provided Q ______is the arrangement made near top of dam for passage of excess water from reservoir. A Sluice way A Spillway A Gallery A Abutments Q Buttress dams are of ______types. A 6 A 4 A 8 A 3 Q The cheapest plant in operation and maintenance is A Steam power plant A Nuclear power plant A Hydroelectric power plant A Diesel power plant Q Which of the following generating station has minimum running cost ? A Nuclear A Hydro A Thermal A Diesel Q Rankine cycle comprises of A two isentropic processes and two constant volume processes A Two isentropic processes and two constant pressure processes A Two isothermal processes and two constant pressure processes A Two isothermal processes and two isentropic processes Q Reheat temperatures are very close to ______temperature A Inlet A Outlet A Intermediate A Critical Q The major use of the economiser is A Heat up the incoming water with exhaust steam. A Heat up the pulverised fuel by exhaust. A Heat up the incoming air by exhaust gases. A Heat up the incoming water by exhaust gases. Q Trapped heat inside the earth is known as______A Heat Energy A Kinetic Energy A A Thermal energy Q For a given value of mean temperature of heat addition (Tm) A Efficiency of Rankine is more if turbine exit temperature(Tmin) is less A Efficiency of Rankine is less if turbine exit temperature(Tmin) is less A Efficiency does not depend on turbine exit temperature A Efficiency depends on turbine exit temperature Q Pressure of steam in condenser is A Atmospheric pressure A More than atmospheric pressure A Slightly less than atmospheric pressure A Much less than atmospheric pressure Q What is the difference between a Rankine cycle & a Brayton cycle? A Working fluid in a Brayton cycle undergoes phase change while it doesn’t in Rankine cycle A Working fluid in a Brayton cycle doesn’t undergo phase change while it does in Rankine cycle A Both are same A Both uses same working fluid Q In Rankine cycle regeneration results in higher efficiency because A Pressure inside the boiler increases A Heat is added before steam enters the low pressure turbine A Average temperature of heat addition in boiler increases A Total work delivered by turbine decreases Q During which of following process does heat rejection take place in Carnot cycle. A Constant pressure A Constant volume A Constant temperature A Constant enthalpy Q Blade erosion in steam turbines takes place A Due to high temperature steam A Due to droplets in steam A Due to high rotational speed A Due to high flow rate Q The main advantage of a reheat Rankine cycle is A Reduced moisture content in L.P side of turbine A Increase efficiency A Reduced load on condenser A Reduced load on pump Q Employing superheated steam in turbines leads to A Increase in erosion of blading A Decrease in erosion of blading A No erosion in blading A No change in erosion of blading In a steam power plant, the ratio of the isentropic heat drop in the prime mover to the amount of heat Q supplied per unit mass of steam is known as A Stage efficiency A degree of reaction A Rankine efficiency A relative efficiency Q A regenerative steam cycle renders A Increased work output per unit mass of steam A Decreased work output per unit mass of steam A Increased thermal efficiency A Decreased work output per unit mass of steam as well as increased thermal efficiency. Q Which one of the following statements is not correct for a regenerative steam cycle? A It increases the thermodynamic efficiency A It reduces boiler capacity for a given output A It reduces temperature stresses in the boiler due to hotter feed A The efficiency increases with increased number of feed heaters Q In thermal power plants the deaerator is used mainly to A Remove air from condenser A Increase feed water temperature A Reduce steam pressure A Remove dissolve gases from feed water heater Q The efficiency of Rankine cycle is lower than that corresponding Carnot cycle because The average temperature at which heat is supplied in Rankine cycle is lower than corresponding A Carnot cycle The Carnot cycle has gas as working substance and Rankine cycle has steam has working substance A The Rankine cycle efficiency depends upon properties of working substance where as Carnot cycle A efficiency is independent of the properties of working substances. A The temperature range of Carnot cycle is greater than that for Rankine cycle. Q In the Rankine cycle lower limit on the condenser pressure is due to the A Expansion limit in turbine A condenser size A Air leakage into the condenser A temperature of cooling water