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Multiple choice question for engineering

Set 1

1. On what aspect is precipitation calculated?
a) Based on hydrological aspect
b) Based on climatic conditions
c) Based on the vegetation of the area
d) Based on weather forecast

View Answer

Answer: a [Reason:] The evaporation of the water from the surfaces of river and oceans and its precipitation on the earth is known as hydrological cycle. Based on hydrological aspect the distribution of precipitation on the earth surface and beneath the earth is calculated.

2. Water evaporated is carried with the air in form of vapor known as _______
a) Cloud
b) Drizzle
c) Fog
d) Smoke

View Answer

Answer: a [Reason:] It is the science which deals with rainfall. Water is evaporated from plants, rivers, oceans and carried with the air in the form of vapor which is known as cloud. Clouds vary in different shape and size and they move according to winds.

3. When does vapor turn into form of water or snow?
a) Cooled below Dew point
b) At Frost point
c) When cooled Freezing point
d) When there is rise in Humidity

View Answer

Answer: a [Reason:] Water is evaporated from surface of earth and stored in form of clouds. When the vapors in the atmosphere are cooled below dew point temperature, it falls in the form of water or snow depending on the atmospheric temperature.

4. What source of energy does evaporation and precipitation consists of?
a) Perennial energy
b) Gravitational energy
c) Thermal energy
d) Kinetic energy

View Answer

Answer: a [Reason:] This evaporation and precipitation is a natural continuous process and therefore constitutes a perennial source of energy. Both these evaporation and precipitation come under the hydrological cycle.

5. Water on the ground surface entering the soil is called _________
a) Infiltration
b) Transpiration
c) Filtration
d) Precipitation

View Answer

Answer: a [Reason:] Infiltration is the process by which water on the ground surface enters the soil. Infiltration rate in soil science is a measure of the rate at which soil is able to absorb rainfall. It is measured in inches per hour or millimeters per hour.

6. The energy input to the hydrological cycle is by ____________
a) Wind
b) Water
c) Sun
d) Head

View Answer

Answer: c [Reason:] The energy input to hydrological cycle is sun. Due to sun, water evaporates from water bodies. On cooling, the vapors form cloud which falls down in the form of rain, snow, hail etc which is known as precipitation.

7. About how much amount of precipitate is returned back to atmosphere?
a) 2/3
b) 1/4
c) 3/4
d) 1/3

View Answer

Answer: a [Reason:] Precipitation includes all water that falls from the atmosphere to earth’s surface in any form. About 2/3 portion of precipitation that reaches land surface is returned back to atmosphere by water surfaces, soil and vegetation.

8. Amount of rainfall which runs off the earth’s land surface to form stream is used for ______
a) Flower generation
b) Back water storage
c) Pit Irrigation
d) Left through canals

View Answer

Answer: a [Reason:] About 2/3 portion of rain is returned back to atmosphere and 1/3 portion is returned back by oceans. The amount of rainfall which runs off the earth’s land surface to form streams and rivers is used for flower generation.

9. What is the unit of runoff ________
a) Day-sec meter
b) M2/s
c) MM/S2
d) Ns/m2

View Answer

Answer: a [Reason:] The unit of runoff is m3/s or Day-second meter. 1 Day second meter = Discharge collected in catchment area at the rate of 1 m3/s or for one day => 1 x 24 x 3600 = 86400 M3/s And Total run off is given by: Total Run-off = Direct runoff over the land surface + Run-off through seepage.

10. Where is the catchment area situated with respect to dam?
a) Behind the dam
b) Front of dam
c) Right beneath the dam
d) Opposite to the Dam Head

View Answer

Answer: a [Reason:] Catchment area of a hydro site is the total area located behind the dam, Draining water into the reservoir. The place is usually steep at this point. And the Dam head acts as outlet point to let out the water after utilizing it for power production.

Set 2

1. What is a relay?
a) A device that resists the flow of Current
b) A device that resists the flow of direction in two ways
c) Device that allows small electrical current to control large electrical current
d) A device that allows the operator to control the current flow in the required direction

View Answer

Answer: c [Reason:] A relay is a device that allows a small amount of electrical current to control a large amount of current. An automobile starter uses a large amount of current to start an engine. If we allow much current to go through the ignition switch, we would need a very large switch.

2. Years ago diesel engines were started with small engines called ________
a) mini engines
b) runty engines
c) pup engines
d) puny engines

View Answer

Answer: c [Reason:] Years ago diesel engines were started with the small engines called pup engines. And another way used to start a diesel engine was by gasoline and switch it over to diesel fuel. A 12v electrical system became very popular and later on they were used.

3. How is minimum cranking speed achieved?
a) By providing the hp
b) By providing speed
c) By providing torque
d) By proving sufficient amount of fuel

View Answer

Answer: c [Reason:] Minimum cranking speed is achieved by providing the necessary torque, which is actually a purpose of starter motor. As the starter motor rotates the flywheel, the crankshaft is turned, which then starts piston movement.

4. Engine cranking is difficult in which temperatures?
a) Moderate
b) Hot
c) Humid
d) Cold

View Answer

Answer: d [Reason:] The engine cranking is difficult in colder temperatures especially if engine is directly driving other machine equipments such as torque converter or hydraulic pumps. Cold engine oil adds to the load on starter, and this load may increase by 3 to 4 times what it would normally be in warmer weather.

5. Which is the recent difficulty added to the starting systems?
a) Fuel flow
b) Gear transmissions
c) Electronic controls
d) Fuel consumption

View Answer

Answer: c [Reason:] The recent difficulty added to the stating system is electronic controls in engines. Some electronic control machines may need some minimum number of revolutions at a minimum speed before energizing the fuel system.

6. If the starter is used properly, for how many starts will it last?
a) About 8000
b) Over 10000
c) Upto 40000
d) At least 25000

View Answer

Answer: b [Reason:] If the starter is used properly, it will last for over 10000 starts. The biggest factor affecting the life of a electric starter is overheating and over-cranking. Never run the starter switch for more than 30 seconds continuously.

7. What is CRDi?
a) Common rail direct infusion
b) Common rail direct injection
c) Common rail diesel injection
d) Common rail diesel infusion

View Answer

Answer: b [Reason:] CRDi id common rail direct injection, which says direct injection of fuel into cylinders via a common single rail called single line which is connected to all the fuel injectors. This system is commonly equipped in diesel engines.

8. What is CDI?
a) Common diesel injection
b) Common direct injection
c) Capacitor discharge ignition
d) Capacitor direct ignition

View Answer

Answer: C [Reason:] CDI stands for capacitor discharge ignition or thyristor ignition is a type of automotive electronic ignition system which is widely used in the outboard motors, motorcycles, chainsaws, lawn mowers and some cars.

9. What does TDI stand for?
a) Turbocharged diesel injection
b) Turbocharged direct injection
c) Turbocharged discharged infusion
d) Turbocharged Direction ignition

View Answer

Answer: b [Reason:] TDI stands for Turbocharged direct injection is a design of turbo diesel engines. These are used in vehicles, also used in the marine engines. In this fuel injector sprays atomized fuel into main combustion chamber of each cylinder.

10. What is GDI engine?
a) Gasoline direct injection
b) Gasoline diesel injection
c) Gasoline discharge injection
d) Gasoline direct infusion

View Answer

Answer: a [Reason:] In non-diesel IC engines, GDI (Gasoline direct injection), also known as petrol direct injection, Fuel satisfied ignition etc. Emission levels can be easily and accurately controlled with diesel systems.

Set 3

1. The process by which plants, some bacteria and some protistans use the energy from sunlight to produce sugar?
a) Taxonomy
b) Metabolism
c) Photosynthesis
d) Osmosis

View Answer

Answer: c [Reason:] Photosynthesis is the process, by which plants, some bacteria and some protistans use the energy from sunlight to produce sugar, which cellular respiration converts into ATP, the fuel used by all living things.

2. What is used in conversion of sunlight energy into usable chemical energy in plants?
a) Anthocyanin
b) Cythochrome
c) Chlorophyll
d) Chitin

View Answer

Answer: c [Reason:] The conversion of usable sunlight energy into usable chemical energy is associated with the actions of the green pigment chlorophyll. Most of the time, photosynthetic process use water and releases the oxygen that we absolutely must have to stay alive.

3. Complete the following reaction:
H2O + CO2
a) 6H2O + 6CO2 → C6H12O6 + 6O2
b) 6H2O + 3CO2 → C6H6O6 + 4O2
c) 6H2O + 6CO2 → C6H12O12 + 12O2
d) 6H2O + 4CO2 → C+ HO3

View Answer

Answer: a [Reason:] 6H2O + 6CO2 → C6H12O6 + 6O22 is the proper form of equation. Six molecules of water + six molecules of carbon dioxide &raar; one molecule of sugar + six molecules of oxygen.

4. Photosynthesis is carried in how many stages?
a) 1
b) 2
c) 3
d) 4

View Answer

Answer: b [Reason:] Photosynthesis is a two stage process. The first process is light dependent process which requires the direct energy of light to make energy carrier molecules that are used in the second process. And the second stage is termed as Dark reaction.

5. Photosynthetic organisms which convert light energy into the chemical energy they need to develop grow, and reproduce are called as?
a) Rubisco
b) Pigment
c) Autotrophs
d) Glucose

View Answer

Answer: c [Reason:] An autotroph or producer, is an organism that produces complex organic compounds (such as carbohydrates, fats, and proteins) from simple substances present in its surroundings, generally using energy from light or inorganic chemical reactions.

6. What is the full form of ATP?
a) Adenosine Tetra-phosphate
b) Adenosine tri-phosphate
c) Adenosine Terra-phosphate
d) Ambient temperature and pressure

View Answer

Answer: b [Reason:] Adenosine tri-phosphate (ATP) is a complex organic chemical that participates in many processes. Found in all forms of life, ATP is often referred to as the “molecular unit of currency” of intracellular energy transfer.

7. What does NADPH?
a) Nicotinamide adenosine deca-nucleotide phosphate
b) Nicotinamide adenine dinucleotide phosphate
c) Nicotinamide adenine deca-nucleotide phosphate
d) Nicotinamide adenosine dinucleo phosphor

View Answer

Answer: b [Reason:] In photosynthetic organisms, NADPH is produced by ferredoxin-NADP+ reeducates in the last step of the electron chain of the light reactions of photosynthesis. It is used as reducing power for the biosynthetic reactions in the Calvin cycle to assimilate carbon dioxide.

8. Which cycle is preferred for production of carbohydrates?
a) Nutrient cycle
b) Bio geo chemical cycle
c) Calvin – Benson Cycle
d) Sonnet cycle

View Answer

Answer: c [Reason:] The Calvin cycle (also known as the Calvin–Benson cycle) is the set of chemical reactions that take place in chloroplasts during photosynthesis. The cycle is light-independent because it takes place after the energy has been captured from sunlight. This cycle is used for the production of carbohydrate.

9. Which is the region within thylakoid where water is split into oxygen?
a) Foramen
b) Serosa
c) Lumen
d) Mucosa

View Answer

Answer: c [Reason:] The lumen is the region within the thylakoid membrane where water is split to obtain oxygen. The oxygen diffuses out of the cell, while the protons remain inside to build positive electrical charge inside the thylakoid.

10. Choose the general formula of carbohydrates?
a) [C2H2O2]n
b) [CHO]n
c) [CH2O]n
d) [C2O2]n

View Answer

Answer: c [Reason:] [CH2O]n is the correct form for representing carbohydrates. Green plants make food in the form of carbohydrates by combining carbon dioxide and water using energy from sunlight. The simplest useful form of carbohydrate produced by photosynthesis is glucose sugar. Glucose may be used as an energy source.

11. Energy plantation does not have any impact on Bio-energy?
a) True
b) False

View Answer

Answer: b [Reason:] Energy plantation means growing select species of trees and shrubs which are harvestable in a comparably shorter time and are specifically meant for fuel. The fuel wood may be used either directly in wood burning stoves and boilers or processed into methanol, ethanol and producer gas.

12.”ATP and NADPH are used to fix CO2 into carbohydrates” this process is termed as ________
a) Carbon fixation
b) Reduction
c) Carbon dating
d) Oxidation

View Answer

Answer: a [Reason:] Carbon fixation or Carbon assimilation is the conversion process of inorganic carbon (carbon dioxide) to organic compounds by living organisms. The most prominent example is photosynthesis, although chemosynthesis is another form of carbon fixation that can take place in the absence of sunlight.

13. The organelle in a plant cell where photosynthesis occurs is called _________
a) Rubisco
b) Chloroplast
c) Thylakoid
d) Pigment

View Answer

Answer: b [Reason:] The main role of chloroplasts is to conduct photosynthesis, where the photosynthetic pigment chlorophyll captures the energy from sunlight and converts it and stores it in the energy-storage molecules ATP and NADPH while freeing oxygen from water.

14. A colored molecule is called ________
a) Epoxy
b) Pigment
c) Gouache
d) Plaster

View Answer

Answer: b [Reason:] Chlorophyll-‘a’ is the primary pigment for photosynthesis in plants, but the range of light absorption is extended by chlorophyll-‘b’, beta-carotene and other accessory pigments. These are present inside a chloroplast.

15. C6H12O6 is a _________
a) Osmophile
b) Trapiche
c) Sugar
d) Butanol fuel

View Answer

Answer: c [Reason:] Glucose is a simple sugar with the molecular formula C6H12O6, which means that it is a molecule that is made of six carbon atoms, twelve hydrogen atoms, and six oxygen atoms. Plants form sugar (glucose) on photosynthesis.

Set 4

The diagram below of Automatic Combustion Control System, is for questions from 1 to 8
energy-engineering-questions-answers-principle-automatic-control-combustion-q1toq-8

1. What is the basis on principle of automatic control of combustion is determined?
a) Control of fuel supply to the boiler
b) Speed of rotation of fans
c) Control of combustion
d) Control of steam pressure

View Answer

Answer: c [Reason:] The principle of automatic control of combustion is derived from the control of combustion. In order to ensure sufficient amount of steam generation at the requisite pressure and to maintain correct proportion of fuel and air in a furnace for complete combustion, control of combustion in the furnace is very much essential.

2. What quantities need to maintained/regulated for effective control of combustion?
a) Induced draught and forced draught fans pressure
b) Air and steam gauge pressure
c ) Fuel flowing out of stoker
d) Air and fuel supply

View Answer

Answer: d [Reason:] Combustion can be effectively controlled by regulating the quantities of air and fuel or both. Control of combustion can be by manual or automatic means. Automatic control of combustion is used to distribute the load evenly on the boiler as per the changing demand.

3. What is necessary to ensure products of combustion flow into the chimney?
a) Air speed
b) Draft in the chimney
c) Differential gas pressure
d) Swirl flow of exhaust air

View Answer

Answer: c [Reason:] In order to ensure products of combustion flow into the chimney at proper speed, it is essential to regulate differential gas pressure in the furnace. In case of automatic control, the controlling devices operate based on the change in pressure of steam.

4. When does automatic control system of combustion come into operation?
a) When there is no fluctuation in furnace draft
b) When there is variation in steam flow rate
c) When the draft connection is clogged
d) When there is minimal amount of air supply

View Answer

Answer: b [Reason:] Automatic control combustion system comes into action when there is variation in steam flow rate also when there is fluctuation in steam pressure and furnace draft. It is safer compared to manual control system and saves manual labour and time.

5. Which is the component that maintains forces in whole automatic combustion control system?
a) Steam pressure gauge
b) Fan vanes
c) Master controller
d) Relay 1 & 2

View Answer

Answer: c [Reason:] Master controller is the component that maintains all the forces in whole system. The actions of primary forces are magnified through the master controller which in turn operates the concerned elements through electric, hydraulic and pneumatic system. The master control makes variation depending on steam pressure level.

6. When does master controller comes into action?
a) When there is variation in steam flow rate
b) When there is variation in fuel supply
c) When there is variation in steam pressure
d) When there is variation in draught fans

View Answer

Answer: c [Reason:] The master controller comes into action when there is variation in steam pressure and it goes down below the required level. This activates the servo motor coupled to the vanes of induced draught fan which opens the air damper slightly. Simultaneously the secondary fan air damper also opens proportionately.

7. When does relay’s 1 and 2 come into operation?
a) When there are changes in steam pressure
b) When there is change in forced draught
c) When there is change in steam flow rate
d) When there is change in induced draught

View Answer

Answer: d [Reason:] When there are variation made in induced draught by air dampers opening due to coupling of motor that’s when relay 1 and 2 comes into operation. Relay 1 operates and adjusts the forced draught fan vanes till stability is restored in the combustion chamber. This result in an increased flow rate of air through the passage P. Due to increased flow rate, relay 2 is actuated which speeds up the stoker motor to supply extra fuel.

8. What is the purpose of Automatic combustion control system?
a) To get constant steam pressure
b) To maintain steady state combustion
c) To get constant steam output
d) To save the time and manual labour.

View Answer

Answer: b [Reason:] The automatic combustion control system provides the effective prevention of the environmental pollution and steady combustion condition to get a constant steam output. But few factors prevent steady combustion condition such as unbalanced combustion air and the movement of the burn-out position in the incinerator.

Set 5

1. How is the coal fed to the grate in over feed system?
a) Above the point of air admission
b) Between the beds of incandescent coke and green coal
c) Above the ash bed
d) Between the point of air admission

View Answer

Answer: a [Reason:] The coal is fed on the grate above the point of air admission. The pressurized air coming from forced draught fan enters under the bottom of the grate. The air passing through the grate is heated by absorbing the heat from the ash and grates itself. Due to this the ash and grate are cooled.

2. The amount of CO2 formed in overfeed system entirely depends on ___________
a) Amount of ash produced
b) Carbon content in fuel
c) Rate of air supply
d) Intensity of process

View Answer

Answer: c [Reason:] The rate of carbon-dioxide entirely depends on the rate of air supply. When the hot air after cooling the ash passes to incandescent coke bed, here the O2 reacts with C to form CO2. Generally for fuel bed of 800mm depth all the O2 in the air is consumed in the incandescent region.

3. Which is the zone where the water vapors carried in air reacts with carbon in over-feed system?
a) Green coal bed zone
b) Incandescent zone
c) Combustion zone
d) At the ash pit

View Answer

Answer: b [Reason:] The water vapour carried with air reacts with Carbon in incandescent zone and forms CO, CO2, and H2. Part of CO2 formed reacts with air C passing through incandescent zone and converts into CO. The gases leaving the incandescent region of fuel bed consist of N2, CO2, CO, H2 and H2O.

4. How is volatile matter of raw coal is lost in the overfeed system?
a) Condensation
b) Distillation
c) Combustion
d) Evaporation

View Answer

Answer: b [Reason:] Raw coal that is continuously supplied on the surface of the bed loses it volatile matter by distillation in this zone. The required for the distillation of coal is given by incandescent coke below the fresh fuel, hot gases diffusing through the surface of the bed and hot gases and flame in the furnace above.

5. Where does the ignition zone lie in overfeed system?
a) Below the raw fuel undergoing distillation
b) Below the combustion zone
c) In between coke bed and flame zone
d) Between coke bed and green coal bed

View Answer

Answer: a [Reason:] The ignition zone lies directly below the raw fuel undergoing distillation. The gases leaving the upper surface of the fuel bed contain combustible volatile matter formed from the raw fuel N2, CO2, O2, H2O and CO if the burning is incomplete.

6. Why is secondary air supplied in overfeed system?
a) To burn the unburnt gases
b) To maintain constant heat intensity
c) To completely remove water vapors formed due to primary air supply
d) To create distillation process for the raw coal supplied

View Answer

Answer: a [Reason:] Additional secondary air is supplied at the top of the bed to burn the remaining combustible gases (volatile matter+CO+H2). The secondary air is supplied at very high speed to create turbulence for complete combustion of unburnt gases.

7. Why does burnt gases with content of N2, CO2, H2, O2 and H2O re-enter the boiler in overfeed system?
a) To dismiss the ash content in the gases formed
b) Due to incomplete burning
c) For complete removal of moisture
d) To complete the burn the coal

View Answer

Answer: b [Reason:] The burnt gases re-enter the boiler containing N2, CO2, O2, H2O and CO if the burning is incomplete. During incandescence, the fuel is continuously loses its carbon by oxidation until only the ash remains.

8. In which direction does fuel, coke and ash in fuel bed move with respect to air and gases in overfeed system?
a) Upward direction
b) Same direction
c) Opposite direction
d) Downward direction

View Answer

Answer: c [Reason:] Fuel, coke and ash in the fuel bed move in the direction opposite to that of air and gases. The primary air entering from the bottom cools the ash until it finally rests in a plane immediately adjacent to the grate.

9. In which direction does fuel and air in under-feed system move?
a) Opposite
b) Across
c) Same direction
d) Counter direction

View Answer

Answer: c [Reason:] In under feed type of stokers, the fuel and air move in the same direction. In this stoker air after passing through the holes in the grate comes in contact with the raw coal. As air diffuses through the bed of raw coal, it mixes with the volatile matter generated by the raw coal.

10. Which is the process from which heat for distillation comes, in under feed system?
a) Conduction
b) Combustion
c) Synthesis reaction
d) Circulation of hot air gases

View Answer

Answer: a [Reason:] The heat for the distillation comes by conduction from the mass of incandescent fuel bed existing above the raw coal. The air mixes with the volatile matter and passes through the ignition zone and then enters into the region of incandescent coke.

11. Which reaction differs over feed and under feed system?
a) Changes occurring in physical properties of the system
b) Breaking of molecular structure
c) Changes in chemical composition
d) Existence of volatile matter

View Answer

Answer: b [Reason:] The reactions which take place in the incandescent zone of under-feed stoker is exactly same as in the incandescent zone of over feed stoker except some breaking of molecular structure of volatile matter. Part of the broken volatile matter reacts with the oxygen of air.

12. What is the purpose of secondary fan’s air in under feed system?
a) To support gases coming out of fuel bed
b) To clear the ash from the upper beds
c) To maintain constant pressure in system
d) To support combustion of system

View Answer

Answer: a [Reason:] The gases coming out of raw fuel bed pass through a region of incandescent ash on the surface of the fuel and finally discharged to the furnace. As the gases coming out of fuel bed also contain combustible matter the supply of secondary air is required in this case. The ash left at the bottom of the stoker is at a higher temperature than the over feed stoker .

13. What is the significance of rate at which air is supplied in the under feed system?
a) Increase depth of incandescent zone
b) Pushes up ignition zone
c) Burns fuel for long time
d) Supports combustion

View Answer

Answer: a [Reason:] The rate of air supply has marked effect on the speed of ignition in case of under feed burning as the rising air cools the raw fuel prior to ignition. At low rate of air fuel, the heat flow by conduction from the incandescent fuel bed downward is faster than the removal of heat by air. This pushes the ignition plane down below the bed surface and creates a maximum depth of incandescent zone.

14. Which type of coal is used in the under feed system?
a) Anthracite coal
b) Bituminous coal
c) Briquette coal
d) Pulverized coal

View Answer

Answer: b [Reason:] The under feed method uses bituminous coals which have high volatile matter. The volatile matter gets heated to a high temperature as it passes through incandescent region of coal. The volatile matter being at a high temperature before entering the furnace burns quickly when mixed with secondary air.

15. Why does over feed burning system takes longer time for complete burning?
a) The volatile matter will be cooler at initial
b) Due to the presence of dust and ash
c) The effect of design of system
d) Effects of air fuels on the system

View Answer

Answer: a [Reason:] In case of over-feed burning, the volatile matter will be considerably cooler than the furnace gases and therefore it requires longer time for complete burning and also the air passes though incandescent zone and then enters ignition zone. This may create a tendency to form smoke.