ELEMENTS 126-250 Flashcards by alyssa everlyn evangelista

What is true about steam as it condenses?

a) It does so at constant entropy and temperature
b) It does so at constant enthalpy and reducing temperature
c) Both enthalpy and entropy reduce and temperature remains constant
d) Both enthalpy and entropy increase

c) Both enthalpy and entropy reduce and temperature remains constant

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It is an increase in fluid pressure in a long pipe caused by a sudden velocity decrease, where the sudden decrease in velocity is caused by a valve closing.

a) Aero dynamics
b) Water hammer
c) Terminal velocity
d) Drag

b) Water hammer

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128.It is an upward force that is exerted on an object (like flat plate, airfoil, rotating cylinder, etc.) as the object passes through a fluid. What do you call this?

a) Drag
b) Lift
c) Aero horsepower
d) Terminal velocity

b) Lift

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What is a frictional force that acts parallel but opposite to the direction of motion of fluid?

a) Drag
b) lift
c) Aero horsepower
d) Terminal velocity

a) Drag

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It is a term used by automobile manufacturers to designate the power required to move a car horizontally at 50 mi/hr against the drag force. What is this?

a) Mechanical horsepower
b) Aero horsepower
c) Fuel power
d) Fluid power

b) Aero horsepower

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131.A manufacturer claims that it has a COP of 2.0 when cooling a food at 5 oC using ambient air at 30 oC as a heat sink. Is the claim of the manufacturer valid?

a) Yes
b) No
c) Probably
d) It needs experimental verification

a) Yes

Note: Yes, because the claimed COP of the manufacturer is lower than the COP of Carnot Refrigeration

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What can you say about the velocity of fluid at the center of the pipe section?

a) Maximum
b) Minimum
c) Average
d) Zero

a) Maximum

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Continuity equation is applicable to which of the following?
a) Viscous and unviscous fluids

b) Compressibility fluids
c) Conservation of mass
d) Steady and unsteady flows

c) Conservation of mass

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Hygrometer is an instrument used to determine of which of the following?

a) Specific gravity of fluids
b) Specific gravity of gases
c) Specific gravity of liquids
d) Specific gravity of solids

a) Specific gravity of fluids

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At critical point of a pure substance, what is the value of latent heat?

a) Maximum
b) Minimum
c) Zero
d) Below zero

c) Zero

note: Zero, at the critical point hg-hf-0

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Which of the following is a function of a steam nozzle?

a) Converts kinetic energy into heat energy
b) Changes internal energy into kinetic energy
c) Converts potential energy into heat energy
d) Changes enthalpic energy into kinetic
energy

d) Changes enthalpic energy into kinetic
energy

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Generally, steam turbines in power station operate at which of the following speeds?

a) 3000 rpm
b) 1000 rpm
c) 4000 rpm
d) 500 rpm

c) 4000 rpm

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Tidal power is the power generated from which of the following?

a) Waves of the ocean
b) Thermal energy of ocean water
c) Raw sea water
d) Rise and fall of tides

d) Rise and fall of tides

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Which of the following is an expression or equivalent of? horsepower per ton of refrigeration?

a) COP/ 4.715
b) 4.715/COP
c) COP x 4.715
d) 1/ (4.715 x COP)

b) 4.715/COP

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140.It is the ratio of the amount of heat taken up by a substance to the temperature at which the substance exists. How do you call this?

a) Internal energy
b) Flow energy
c) Enthalpy
d) Entropy

d) Entropy

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Which of the following is a type of water turbine where a jet of water is made to fall on the blades or buckets and due to the impulse of water the turbine starts moving?

a) Reaction turbine
b) Steam turbine
c) Francis turbine
d) Pelton wheel

d) Pelton wheel

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What do you call a fan in which the fluid is accelerated parallel to the fan axis?

a) Axial centrifugal fan
b) Mixed flow centrifugal fan
c) Radial centrifugal fan
d) Francis type fan

a) Axial centrifugal fan

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It represents the loss due to mechanical friction of the moving parts of the engine, and expressed as horsepower. How do you call this?

a) Indicated Hp
b) Brake Hp
c) Combined Hp
d) Friction Hp

d) Friction Hp

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How do you call a device or engine which continually and indefinitely discharged more energy than it receives?

a) Carnot engine
b) Generating machine
c) Stirling engine
d) Perpetual motion machine

d) Perpetual motion machine

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In plotting the bHp versus speed in a wide- open throttle test for a spark ignition engine, the bHp curve:

a) is a Straight line.
b) tends to concave downward
c) has no characteristic shape
d) tends to concave upward

b) tends to concave downward

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Upon entering the boiler room, you find the water out of the glass, the safety valve blowing off strong, and a fire under the boiler. Your first action would be to:

a) Remove the fire with draft and damper open
b) Cool the boiler down completely
c) Prevent priming by not raising the safety valve or making change in operating of engines or boiler
d) Cool the boiler down completely and prevent priming by not raising the safety valve

a) Remove the fire with draft and damper open

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The A.S.M.E. Boiler code for boiler shells requires a tensile strength of which of the following, in psi?

a) 10000 to 20000
b) 25000 to 45000
c) 55000 to 63000
d) 70000 to 85000

c) 55000 to 63000

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The best time to blow a boiler down is:

a) Once a day when the load is lightest
b) Once a day under full load
c) When the chemical concentration is greatest
d) Once a shift

a) Once a day when the load is lightest

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149.In performing a hydrostatic test on an existing power boiler, the required test pressure must be controlled so that it is not exceeded by more than:

a) 2%
b) 4%
c) 6%
d) 8%

b) 4%

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150.The first step to take in planning a preventive maintenance program is to: a) Replace all electric wiring b) Make an equipment inventory c) Replace all pump seals d) Repair all equipment which is not in operation

d) Repair all equipment which is not in operation

151. Which of the following is the most important consideration in a fire prevention program? a) Train the staff to place flammable in fireproof containers b) Know how to attack fires regardless of size c) See that halls, corridors, and exits are not blocked d) Detect and eliminate every possible fire hazard

d) Detect and eliminate every possible fire hazard

152. Which of the following types of portable fire extinguisher is recommended as most effective for putting out oil fires? a) Pump tank type b) Cartridge actuated type c) Soda acid type d) Foam type

b) Cartridge actuated type

153. Which of the following are the four stages of the warning system designated by the high air pollution alert warning system? a) Initial, chronic, acute, penetrating b) Forecast, alert, warning, emergency c) light, medium, heavy, extra heavy d) Early, moderate, severe, toxic

a) Initial, chronic, acute, penetrating

154. The chemical most commonly used to speed sedimentation of sewage is known as: a) Lime b) Copper sulfate c) Sulfuric acid d) Methylene blue

a) Lime

155.Most of the bacteria in sewage are: a) Saprophytic b) Dangerous c) Parasitic d) Pathogenic

a) Saprophytic

156. One of the two types of non-material nuclear radiation is: a) Gamma radiation b) Transmutation radiation c) Walton radiation d) Betatron radiation

a) Gamma radiation

157. Which of the following is not a qualification for an applicant for ME board examination? a) A certified plant mechanic b) At least 18 years old c) A holder of BSME degree d) A citizen of the Philippines

a) A certified plant mechanic

158. A thermo hydraulic feed water regulator is used to regulate the flow of water to a drum type boiler. The amount of water input to the boiler is controlled in proportion to the: a) Boiler load b) Setting of the feed pump relief valve c) Amount of water in the outer tube that flashes into steam d) Water level in the drum

d) Water level in the drum

159. The standard capacity rating conditions for any refrigeration compressor is: a) 50F, 19.6 psig for the suction 860F, 154.5 psig for the discharge b) 50F, 9.6 psig for the suction 960F, 154.5 psig for the discharge c) 100F, 9.6 psig for the suction 960F, 144.5 psig for the discharge d) 50F, 19.6 psig for the suction 960F, 134.5 psig for the discharge

a) 50F, 19.6 psig for the suction 860F, 154.5 psig for the discharge

160. In accordance with the air pollution control code, no person shall cause or permit the emission of air contaminants from a boiler with a capacity of 500 million BTU sulfur dioxide content of more than: a) 300 parts per million by volume undiluted emissions measured at 15 percent excess air b) 200 parts per million by volume of undiluted emissions measured at 10 percent excess air c) 200 parts per million by volume undiluted emissions measured at 15 percent excess air d) 300 per million by volume undiluted emissions measured at 10 percent excess air

b) 200 parts per million by volume of undiluted emissions measured at 10 percent excess air

161. Assume that one of your assistances was near the Freon 11 refrigeration system when a liquid Freon line ruptured. Some of the liquid Freon 11 has gotten into your assistant's right eye. Of the following actions, the one which you should not take is to: a) Immediately call for an eye doctor specialist (medical doctor) b) Gently and quickly rub the Freon 11 out of the eye c) Uses a boric-acid solution to clean out the Freon 11 from his eye d) Wash the eye by gently blowing the Freon 11 out of his eye with air

b) Gently and quickly rub the Freon 11 out of the eye

162.As compared to a power-driven triplex single-acting pump of the same size and operating at the same speed, a steam-driven duplex double-acting pump will: a) Pump more water per minute b) Give a more uniform discharge c) Have a higher first cost d) Be more economical to operate

a) Pump more water per minute

163.It is a device commonly used to cool condenser water in Power and Refrigeration plants. The function of which is to reject heat to the atmosphere by reducing the temperature of water circulated through condenser or other heat rejection equipment. What is this device commonly called? a) Condenser b) Cooler c) Cooling tower d) Evaporator

c) Cooling tower

164. It is a type of dryer in which the gases of combustion pass through the spaces surrounding, or in other ways heating, the drying chamber, but the gases are not allowed in contact with the material being dried. What is this dryer? a) Direct-heat type dryer b) Indirect-heat type dryer c) Steam-heated type dryer d) Rotary Dryer

b) Indirect-heat type dryer

165. In a refrigeration system, which of the following would cause a high suction pressure? a) Expansion valve not open wide enough b) Expansion valve open too wide c) King valve not open wide enough d) Dirty dehydrator

b) Expansion valve open too wide

166. In the deep well installing or operation, the difference between static water level and operating water level is called: a) Suction lift b) drawdown c) priming level d) clogging

b) drawdown

167. Which of the following is a characteristic of an impulse turbine? a) Steam striking blades on angle b) No steam reaction to velocity c) Steam striking blades at zero angle d) Steam reversing direction

c) Steam striking blades at zero angle

168. Gas produced by the combustion of fuel oil and cannot be found in the flue gases is: a) Carbon dioxide b) Hydrogen c) Oxygen d) Nitrogen

b) Hydrogen

169. Scale in boiler can: a) Create low steam quality b) Cause foaming c) Overheat blow off line d) Inhibit circulation and heat transfer

d) Inhibit circulation and heat transfer

170. The effectiveness of a body as a thermal radiator at a given temperature: a) Absorptivity b) Emissivity c) Conductivity d) Reflectivity

b) Emissivity

171. To protect adequately the engine bearings, what type and better arrangement of lubricating oil filter is most practical? a) Full flow type filter installed between the lubricating oil pump and bearings b) Splash lubricating system in the crank case c) Duplex filter installed before the lubricating pump d) Bypass filter with cleanable and replaceable elements

a) Full flow type filter installed between the lubricating oil pump and bearings

172. When the expansion or compression of gas takes place without transfer of heat t or from the gas, the process is called: a) Reversible b) Adiabatic c) Polytrophic d) Isothermal

b) Adiabatic

173. Which of the following is other name for the liquid valve? a) Freon valve b) shut off valve c) King valve d) Master valve

c) King valve

174. In accordance with recommended maintenance practice, thermostats used in a pneumatic temperature control system should be checked: a) Weekly b) Bi-monthly c) Monthly d) Once a year

d) Once a year

175. Of the following, the best method used to determine the moisture level in a refrigeration system is to: a) Weigh the driver after it has been in the system for a period of time b) Use a moisture indicator c) Visually check the sight glass for particles of corrosion d) Test a sampler lubricating oil with phosphorus pentoxide

b) Use a moisture indicator

176.A full-flow drier is usually recommended to be used in in a hermetic refrigeration compressor system to keep the system dry and to: a) Prevent the products of decomposition from getting into the evaporator in the event of motor burn-out b) Condense out liquid refrigerant during compressor off cycles and compressor start-up c) Prevent the compressor unit form decreasing in capacity d) Prevent the liquid from dumping into the compressor crank-case

a) Prevent the products of decomposition from getting into the evaporator in the event of motor burn-out

177. You are supervising the installation of a steam-driven reciprocating pump. The pump's air chamber is missing and you have to replace it with one of several salvaged ones. The salvaged air chamber selected should have a volume equal to, most nearly, a) Half of the position displacement of the pump b) 11⁄2 times the position displacement of the pump c) 2 times the piston displacement of the pump d) 2 1⁄2 times the piston displacement of the pump

d) 2 1⁄2 times the piston displacement of the pump

178. Economical partial-load operation of steam turbines is obtained by minimizing throttling losses. This is accomplished by: a) Reducing the boiler pressure and temperature b) Throttling the steam flow into the uncontrolled set of nozzles c) Dividing the first-stage nozzles into several groups and providing a steam control valve for each group d) Controlling the fuel flow to the steam generator

c) Dividing the first-stage nozzles into several groups and providing a steam control valve for each group

179.How do you compare superheated steam to that of saturated steam at the same pressure? a) Contains more heat energy b) Has a greater enthalpy of evaporation c) Has a smaller specific volume d) Condenses at a higher temperature

a) Contains more heat energy

180. Which of the following is not characteristic of superheated steam? a) It contains no water droplets b) It causes severe erosion in pipes c) It may cause uneven heating of a product d) It has a temperature greater than 165C

b) It causes severe erosion in pipes

181.Superheated steam at a pressure of 6 bar g: a) Has a larger Specifc heat capacity than water b) Has a dryness fraction of 0.99 c) Must not be used as a heat transfer medium d) Has a temperature greater than 165 oC

d) Has a temperature greater than 165 oC

182.Of the following, the main purpose of a sub- cooler in a refrigerant piping system for a two-stage system is to: a) Reduce the total power requirements and total heat rejection to the second stage b) Reduce the total power requirements and return oil to the compressor c) Improve the flow of evaporator gas per ton and increase the temperature d) Increase the heat rejection per ton and avoid system shutdown

a) Reduce the total power requirements and total heat rejection to the second stage

183.In large refrigeration systems, the usual location for charging the refrigeration system is into the: a) Suction line b) Liquid line between the receiver shut-off valve and the expansion valve c) line between the condenser and the compressor d) line between the high-pressure cut-off switch and the expansion valve

b) Liquid line between the receiver shut-off valve and the expansion valve

184.The effect of a voltage variation to 90 percent of normal voltage, for a compound wound DC motor, of the full load current is: a) Increase in the full load current approximately by 10% b) Zero c) A decrease in the full load current of approximately 10% d) A decrease in the full load current 20%

a) Increase in the full load current approximately by 10%

185.The main advantage of operating a steam engine or steam turbine "condensing" is that it: a) Increases the mean effective pressure in the prime mover b) Decrease the condensate temperature c) Permits the use of exhaust steam to drive auxiliary equipment d) Eliminates the need for separating non- condensable from the steam

a) Increases the mean effective pressure in the prime mover

186.The automatic shut off valves for a water gage installed on a high-pressure boiler must be: a) Horizontal swing-check valves b) Vertical swing-check valves c) Ball-check valves d) Spring-loaded check valves

c) Ball-check valves

187.The efficiency of a riveted joint is defined as the ratio of the: a) Plate thickness to the rivet diameter b) Strength the riveted joint to the strength of a welded joint c) Strength of the riveted joint to the strength of the solid plate d) Number of rivets in the first row of the joint to the total number of rivets on one side of the joint

c) Strength of the riveted joint to the strength of the solid plate

188.It corresponds to a heat absorption rate of 237.6 Btu/min (4.175 kW) with inlet an outlet pressures corresponding to saturation temperature of 23 oF (-5 oC) and 59 oF (15OC), respectively. How do you call this absorption rate? a) American Unit of refrigeration b) British Unit of refrigeration c) European Unit of refrigeration d) Standard Unit of refrigeration

b) British Unit of refrigeration

189. What is the advantage of an internal water level control over an external one? a) The external control is in a 'dead' area b) It is less likely to scale up c) It will respond more quickly to changes in water level d) Daily testing of the level control chamber is not required

d) Daily testing of the level control chamber is not required

190. What is the purpose of testing gauge glasses? a) To ensure the gauge cocks are operative b) To ensure there is sufficient water over the top fire tube c) To ensure the boiler water level is being properly sensed d) To check the boiler 1st and 2nd low water level alarms

a) To ensure the gauge cocks are operative

191. What is the effect of an overloaded boiler? a) Water level rises and lock-out occurs b) Reduced steam production c) Water level drops and lock-out occurs d) Steam velocity reduces and separator efficiency drops

c) Water level drops and lock-out occurs

192. Why is slow, controlled warm-up of a steam system essential? a) To make it easier to open the boiler main stop valve b) To minimize undue stresses and eliminate damage c) To permit separators to remove more water d) To prevent stress on the boiler

b) To minimize undue stresses and eliminate damage

193. Which of the following is the main purpose of the steam distribution manifold? a) It replaces the need for a separator after the boiler b) to remove air from the steam system c) To provide an extra separating function d) It is a requirement of the pressure systems regulations

c) To provide an extra separating function

194.Priming of a boiler is: a) Getting a boiler prepared for start-up b) A reduction in boiler pressure and carryover of water c) Occurrence of excessive TDS and carryover of water d) Balancing of boilers in a multi-boiler installation

c) Occurrence of excessive TDS and carryover of water

195. What is the advantage of interruptible tariff? a) Quick and easy to change to heavy fuel oil when required b) Price of fuel c) Price of interruptible gas lower than fixed supply d) Convenience of supply

c) Price of interruptible gas lower than fixed supply

196. At what pressure should a boiler safety valve be set? a) Maximum working pressure b) Normal working pressure c) Hydraulic test pressure d) Feed pump maximum pressure

a) Maximum working pressure

197. What is the purpose of a bottom blowdown valve? a) To control water level b) To drain the boiler c) To maintain TDS d) To remove sludge

d) To remove sludge

198.How often, as a minimum, should gauge glasses be tested? a) Once a shift b) Twice a day c) Once a day d) Once a week

c) Once a day

199. Why are two-gauge glasses often fitted? a) One is a check against the other b) One is a reserve c) It is a legal requirement d) To increase periods between maintenance

c) It is a legal requirement

200. Temporary hardness salts are reduced by: a) Raising the water temperature b) lowering the water temperature c) Raising the pH value d) letting the water settle

a) Raising the water temperature

201.What is the effect of CO2 in a steam system? a) The formation of scale b) The formation of sludge c) Corrosion d) Acidity

c) Corrosion

202. Which of the following forms soft scale or sludge? a) Magnesium sulphate b) Sodium carbonate c) Sodium bicarbonate d) Calcium bicarbonate

d) Calcium bicarbonate

203. Which of the following are principal dissolved solids that are scale forming? a) Carbonates and sulphates of sodium b) Calcium bicarbonate c) Carbonates and sulphates of magnesium d) Bicarbonate of sodium and magnesium

c) Carbonates and sulphates of magnesium

204. What is the effect of temperature on calcium and magnesium sulphates? a) They separate out as soft scale and sludge b) They precipitate out solution and form hard scale c) Foaming and carryover occurs d) The TDS is increased

b) They precipitate out solution and form hard scale

205. What is the treatment for scale forming salts in boiler feedwater? a) They are chemically treated to modify the pH b) The feedwater tank is raised to at least 85OC c) They are chemically treated to produce suspended solids d) They are removed by filtration means

c) They are chemically treated to produce suspended solids

206. Which of the following types of alcohol is the most frequently considered as fuel for internal combustion engine? a) Methyl alcohol b) Isopropyl alcohol c) Ethyl alcohol d) Alcogas

c) Ethyl alcohol

207. In a thermal plant, name the components of a self-acting temperature control system. a) Control valve and actuator b) Control valve, actuator and sensor c) Control valve, actuator, capillary tube and sensor d) Control valve, actuator and capillary tube

c) Control valve, actuator, capillary tube and sensor

208. What is the purpose of over temperature protection within the self-acting control system? a) To protect the valve from high temperature steam b) To protect the liquid fall in the capillary from boiling c) To protect the control system from irreversible damage d) To protect the application from overtemperature

c) To protect the control system from irreversible damage

209. Why are three-port self-acting control valves used in an industrial steam of a thermal system? a) To mix or divert liquids especially water b) To dump steam to waste under fault conditions c) Where cooling applications are required d) When large valves are required to meet large capacities

a) To mix or divert liquids especially water

210.How do you call a process in which superheated steam is either restored to its saturated state, or its superheated temperature is reduced? a) Superheating b) Reheating c) Regenerative heating d) Desuperheating

d) Desuperheating

211.What does MAWP stand for? a) Maximum attenuated working pressure b) Maximum allowable working pressure c) Maximum allowable with pressure d) Minimum allowable working pressure

b) Maximum allowable working pressure

212.Name one disadvantage of a direct acting pressure reducing valve. a) It only has proportional control b) It has proportional and integral control but no derivative control c) It operates in an on/off fashion d) An external power source is required for it to operate

a) It only has proportional control

213.In order to avoid cavitation in a centrifugal pump, which of the following is true? a) Installation NPSH ≥ pump NPSH b) Installation NPSH ≤ pump NPSH c) Installation NPSH < pump NPSH d) Installation NPSH should be negative

c) Installation NPSH < pump NPSH

214.It is dust removal equipment that consists of a cylindrical tank structure provided with a tangential opening at one end for gas passage and a spray manifold at the center which is made of a vertical pipe attached with spray nozzles where water is introduced at the bottom of this spray pipe. The gas revolves around the cylindrical body as it enters the scrubber, and comes in contact with the water spray, the dust fly ash is then wetted and hence separated from the gas leaves the scrubber at the top. a) Cinder trap or catcher b) Cyclonic Spray Scrubber c) Cyclone Separator d) Electrostatic Precipitator

b) Cyclonic Spray Scrubber

215. What is a heat exchanger that allows cross contact between two media? This heat exchanger allows the cooling water to flow by gravity over the outside of tubes or plates. a) Single-pass heat exchanger b) Double-pass heat exchanger c) Baudelot heat exchanger d) Shell-and-tube heat exchanger

c) Baudelot heat exchanger

216. What is the recommended weight of the machine foundation? a) 3 to 5 times the machine weight b) 4 to 6 times the machine weight c) 2 to 4 times the machine weight d) 2 to 4 times the machine weight

a) 3 to 5 times the machine weight

217.It is a bituminous coal that contains plenty of hydrocarbons, forming lumped masses when burned. This coal is ideal for forming carbonaceous gases for reduction of ore. What do you call this coal? a) Coking or coking coal b) Free burning coal c) Peat coal d) lignite coal

a) Coking or coking coal

218.It is an engine in which the connecting rod is directly connected to the piston wristpin. The side thrust caused by the angularity of the connecting rod is taken by the piston bearing against the cylinder wall. a) Opposed-piston engine b) Trunk piston engine c) Crosshead engine d) 2-stroke engine

b) Trunk piston engine

219.It is an internal combustion engine wherein the ignition of the fuel is not accomplished solely by the heat developed from the compression of the combustion air supplied but partly or entirely by other heat sources, such as an uncooled tube, plate, bulb or an electric resistance coil. a) Spark-ignition engine b) Compression-ignition engine c) Surface-ignition engine d) Dual combustion engine

c) Surface-ignition engine

220.This is the condition in a geothermal plant wherein the ground surface where the drilled well is depressed or subsides due to depleting. What do you call this? a) Ground subsidence b) Thermal pollution c) Chemical pollution d) Dissolved solids

a) Ground subsidence

221.In the critical thickness of insulator concept for a cylinder, what does the Biot number indicate if its value is less than 1? a) Condition for optimum heat flow b) Addition of insulation will increase heat transfer rate c) Additional insulation will decrease the heat transfer rate d)Heat transfer rate reaches a maximum

b) Addition of insulation will increase heat transfer rate

222.How do you call the ratio of the product of a convective heat transfer coefficient and the critical radius of the insulator to that of the thermal conductivity of the insulator? a) Biot number b) Prandtl number c) Nusselt number d) Reynolds number

a) Biot number

223.This is a type of dryer that consists of a vertical shaft in which the wet feed is introduced at the top and falls downward over baffles while coming in contact with the hot air that rises and exhaust at the top. This dryer is used for drying palay, wheat, and grains. a) Rotary dryer b) Hearth dryer c) Tower dryer d) Tray dryer

c) Tower dryer

224.How do you call those substances that are particularly variable in the moisture content that they can possess at different times? a) Wet materials b) Hygroscopic materials c) Gross materials d) Bone-dry-weight material

b) Hygroscopic materials

225. The bottom blows down on a boiler is used to: a) Remove mud drum water impurities b) Increase boiler priming c) Reduce steam pressure in the header d) Increase the boiler water level

c) Reduce steam pressure in the header

226.In a Brayton cycle or gas turbine cycle, what do you call the heat exchanger that passes exhaust heat to the compressed air, prior to combustion? a) Reheater b) Recuperator c) Heater d) Heat exchanger

b) Recuperator

227.The heat rejected by the working substance to the regenerator in the Stirling cycle is: a) Equal to the heat absorbed by the working substance from the regenerator b) Not equal to the heat absorbed by the working substance from the regenerator c) Dependent on the value of temperature in the heat addition process d) Measured during the constant temperature heat rejection process

a) Equal to the heat absorbed by the working substance from the regenerator

228.How do you call a device that converts liquid refrigerant to vapor, with the held of the surrounding heat? a) Condenser b) Expansion valve c) Compressor d) Evaporator

d) Evaporator

229.In gas compressor, when the volumetric efficiency increases, the piston displacement has: a) Not been changed b) Been decreased c) Been increased d) Been insufficient data

b) Been decreased

230. The ratio of its radiating power to that of a black body at same temperature. a) Transmissivity b) Reflectivity c) Absorptivity d) Emissivity

d) Emissivity

231.Fans used to withdraw air under suction, that is, the resistance to gas flow is imposed primarily upon the inlet. a) Blowers b) Exhauster c) industrial fans d) Domestic fans

b) Exhauster

232.The phenomenon of rising water in the tube of small diameter is called what? a) Surface tension b) Capillary rise c) Water gage rise d) Fluid column rise

b) Capillary rise

233.Pitot tube is used to measure. a) Height b) Velocity c) Viscosity d) Density

b) Velocity

234. During engine operation, to vary the air quantity and also to vary the air fuel mixture, this is used to pen and closed the inlet manifold. a) Throttle valve b) Check valve c) Choke valve d) Gate valve

b) Check valve

235. It deals only with the motion of bodies without reference to the forces that cause them. a) Kinetics b) Motion c) Kinematics d) Acceleration

a) Kinetics

236. Progressive change in position of a body is called: a) Acceleration b) Motion c) Force d) Momentum

c) Force

237. Cam in general maybe divided into two classes; uniform motion and motion cam. a) Reverse b) gravity c) decelerated d) accelerated

d) accelerated

238. Product of mass and linear velocity is known as: a) Impulse b) Linear momentum c) Angular momentum d) Impact

b) Linear momentum

239. It is the motion of an object diminished/decreased speed. a) Deceleration b) Retarded motion c) Negative impulse d) All of these

b) Retarded motion

240. It is a property of matter, which causes it to resist any change in its motion or state of rest. a) Brake b) Friction c) Inertia d) Impulse

c) Inertia

241. If the velocity of mass is the same all the time during which motion takes place is called: a) Deceleration b) Uniform motion c) Acceleration d) None of these

b) Uniform motion

242. Statement that a given body is in static equilibrium means that the body cannot a) have any type of motion b) be acted upon by more than one force c) undergo any displacement d) have any type of acceleration

a) have any type of motion

243. It is a science of motion that can be solved in terms of scalar or vector algebra. a) Kinematics b) Curvilinear translation c) Projectile d) Acceleration

a) Kinematics

244. An object thrown upward will return to earth the magnitude of the terminal velocity equal to a) zero b) one-half the initial velocity c) twice the initial velocity d) initial velocity

d) initial velocity

245. The follower reciprocates or oscillates in a plane perpendicular to the axis of rotation of the cam. a) Radial cam b) Cylindrical cam c) Cam curves d) Tangential cam

a) Radial cam

246. The follower reciprocates or oscillates in a plane parallel to the axis of rotation. a) cam curves b) cylindrical cam c) tangential cam d) Radial cam

a) cam curves

247. A cone formed by elements, which are perpendicular to the elements of the pitch cone at the large end. a) cone distance b) back cone c) root cone d) cone center

b) back cone

248. The ability of moving body to perform work is called: a) Internal energy b) potential energy c) kinetic energy d) flow work

c) kinetic energy

249. A slider crank chain is made up of a) one turning and one sliding pair b) one turning and two sliding pairs c) two turning and one sliding pair d) three turning and one sliding pair

d) three turning and one sliding pair

250. A Scott-Russell mechanism is made a) rotating pair only b) sliding and turning pairs c) turning and rotary pairs d) turning pair only

b) sliding and turning pairs

ELEMENTS 126-250 Flashcards

(125 cards)