2201. Standard air is the air at_____________________?
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A. 25C, 1 kg/cm2 and RH of 60%.

B. 15C and 1 kg/cm2

C. 20C and 1 kg/cm2 and relative humidity 36%

D. 0C and standard atmospheric conditions

E. atmospheric conditions at any specific location

2202. If V, U and Vr represent the absolute velocity of fluid, velocity of blade, and relative velocity of fluid, and suffix i and o stand for entry and exit conditions, then in a rotary machine whose degree of reaction is unity______________?
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A. Vi=V0B

B. U,<V0

C. Vri=Vm

D. Vt>V0

E. V,= U0

2203. For speed above 3000 km/hour, it is more advantageous to use____________________?
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A. rockets

B. turbo-jet engine

C. hydraulic jet propulsion

D. propellers

E. ram-jet engine
2204. The ratio of specific weighf/h.p. of gas turbin and I.C engines may be typically of the order of_______________________?
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A. 4:01

B. 2:01

C. 1:01

D. 1 : 6

E. 1:02

2205. Temperature of gases at end of compression as compared to exhaust gases in a gas turbine is_________________?
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A. cant be compared

B. unpredictable

C. equal

D. higher

E. lower
2206. Losses in a centrifugal compressor are due to__________________?
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A. diffuser losses

B. all of the above

C. inlet losses

D. none of the above

E. impeller channel losses

2207. Pick up the wrong statement ?
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A. axial flow compressors have instability region of operation

B. axial flow compressors are more stable than centrifugal type compressors but not as efficient

C. axial flow compressors have high capacity and efficiency

D. large gas turbines employ axial flow compressors

E. centrifugal compressors are used mainly on low flow pressure ratio gas turbines

2208. The hottest point in a gas turbine is______________________?
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A. uniformly heated

B. at the base

C. at the tip

D. between ~ to i of the blade height

E. in the center

2209. As the value of index is decreased, the volumetric efficiency will___________________?
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A. may increase/decrease depending on compressor clearance

B. decrease

C. remain unaffected

D. increase

E. none of the above

2210. Water gas is produced by ___________________ ?
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A. same way as the natural gas

B. partial combustion of caol, eke, anthractie coal or charcoal in a mixed air steam blast

C. passing steam over incandescent coke

D. carbonisation of coal

E. passing air and a large amount of steam over waste coal at about 65C

2211. A rocket engine for the combustion of its fuel_____________________?
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A. does not require oxygen

B. uses surrounding air

C. depends on electrical energy supplied by solar cells

D. carries its own oxygen

E. uses compressed atmospheric air

2212. The pressure ratio for an open cycle gas turbine compared to closed cycle gas turbine of same h.p. is_______________?
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A. low/high depending on make and type

B. low

C. unpredictable

D. high

E. same

2213. For a two stage compressor* if index of compression for higher stage is greater than index of compression for lower stage, then the optimum pressure as compared to ideal case will___________________?
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A. increase

B. decrease

C. unpredictable

D. remain unaffected

E. other factors control it

2214. Actual compression curve is___________________?
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A. in between isothermal and adiabatic

B. better than isothermal and adiabatic

C. none of the above

D. same as adiabatic

E. same as isothermal

2215. In a compressor, free air delivered is the actual volume delivered at the stated pressure reduced to ____________________?
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A. intake temperature and pressure conditions

B. N.T.P. conditions

C. none of the above

D. 20C and 1 kg/cm2

E. 0C and 1 kg/cm2

2216. Pick up the wrong statement about advantages of multistage compression____________________?
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A. mechanical balance is better

B. better lubrication is possible advantages of multistage

C. more loss of air due to leakage past the cylinder

D. more uniform torque, light cylinder and saving in work

E. air can be cooled perfectly in between

2217. Which of the following plants is smallest and lightest for genrating a given amount of power__________________?
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A. steam power plant

B. gas turbine plant

C. solar plant

D. diesel engine

E. petrol engine

2218. 1 m of air at atmospheric condition weighs approximately__________________?
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A. 0.5 kg

B. 1.0 kg

C. 2.2 kg

D. 1.3 kg

E. 3.2 kg

2219. The following property is most important for material used for gas turbine blade___________________?
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A. bulk modulus

B. toughness

C. fatigue

D. corrosion resistance

E. creep
2220. Propulsive efficiency is defined as ratio of___________________?
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A. thrust power and fuel energy

B. thrust power and propulsive power

C. propulsive power and fuel input

D. none of the above

E. engine output and propulsive power

2221. After-cooler is used to__________________?
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A. increase pressure

B. decrease the delivery temperature for ease in handling

C. cool the air

D. cause moisture and oil vapour to drop out

E. reduce volume

2222. In multistage compressor, the isothermal compression is achieved by_________________?
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A. by running compressor at very slow speed

B. employing intercooler

C. by constantly cooling the cylinder

D. none of the above

E. by insulating the cylinder

2223. Air-fuel ratio in a jet engine will be of the order of__________________?
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A. 20:01

B. 100:00:00

C. 60 : 1

D. 15:01

E. 10:01

2224. The pressure ratio of an ideal vaned compressor with increase in mass flow rate_________________?
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A. remains constant

B. first decreases and then increases

C. unpredictable

D. decreases

E. increases

2225. Which is false statement about multistage compression ?
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A. Outlet temperature is reduced

B. It is best suited for compression ratios around 7:1

C. Power consumption per unit of air delivered is low

D. Volumetric efficiency is high

E. The moisture in air is condensed in the intercooler

2226. The power available for take off and climb in case of turbojet engine as compared to reciprocating engine is ___________________?
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A. more

B. less

C. same

D. unpredictable

E. may be less or more depending on ambient conditons

2227. Which of the following fuels can be used in turbojet engines _____________________?
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A. liquid hydrogne

B. high speed diesel oil

C. kerosene

D. demethylated spirit

E. methyl alcohol

2228. The ratio of the increase in pressure in rotor blades to total increase in pressure in the stage is called__________________?
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A. pressure coefficient

B. degree of reaction

C. slip factor

D. pressure ratio

E. stage factor

2229. The thermal efficiency of a gas turbine as compared to a diesel plant is__________________?
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A. less

B. depends on other factors

C. same

D. unpredictably

E. more

2230. The specific output per kg mass flow rate of a gas turbine (having fixed efficiencies of compressor and turine and fixed higher and lower temperature) with increase in pressure ratio will___________________?
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A. none of the above

B. first increase, reach maximum and then decrease

C. increase first at slow rate and then fast

D. increase first at fast rate and then slow

E. decrease continuously

2231. Turbofan engine employs ____________________ ?
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A. two or more air streams

B. rocket principle for its operation

C. one air stream

D. solid fuel firing

E. no air stream

2232. As the turbine inlet temperature increases, the thermal efficiency of gas turbine for the optimum pressure ratio_____________________?
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A. first increases and then decreases

B. remains same

C. decreases

D. first decreases and then increases

E. increases
2233. The effective power of gas turbines is increased by adding the following in compressor__________________?
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A. hydrogen

B. ammonia and water vapour

C. none of the above

D. nitrogen

E. carbon dioxide

2234. In gas turbines^ high thermal efficiency is obtained in_________________?
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A. closed cycle

B. open cycle

C. both of the above

D. closed/open depending on other con-siderations

E. unpredictable

2235. The main purpose of reheating in gas turbine is to__________________?
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A. increase pressure ratio

B. increase power output

C. reduce turbine size

D. increase speed

E. increase temperature

2236. Mining industry usually employs following motive power___________________?
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A. diesel engine

B. D.C. electric motor

C. compressed air

D. A.C. electric motor

E. petrol engine

2237. The net work input required for compressor with increase in clearance volume_____________________?
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A. unpredictable

B. remains same

C. increases

D. increases/decreases depending on com-pressor capacity

E. decreases

2238. Ram-jet engine__________________?
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A. is self-operating at zero flight speed

B. is not self-operating at zero^flight speed

C. none of the above

D. requires no air for its operation

E. produces a jet consisting of plasma

2239. Gas turbine works on_______________?
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A. Erricsson cycle

B. Brayton or Atkinson cycle

C. Rankine cycle

D. Joule cycle

E. Carnot cycle

2240. Gas turbine works on______________?
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A. Brayton or Atkinson cycle

B. Joule cycle

C. Carnot cycle

D. Erricsson cycle

E. Rankine cycle

2241. Diffuser in a compressor is used to _____________________?
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A. increase degree of reaction

B. increase velocity

C. convert kinetic energy into pressure energy

D. make the flow stream-line

E. convert pressure energy into kinetic energy

2242. Turbo propeller has the following additional feature over the turbojet __________________?
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A. intercooler

B. peopeller

C. diffuser

D. starting engine

E. turbine and combustion chamber

2243. To avoid moisture troubles, the branch connections from compressed air lines should be taken from_________________?
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A. any location

B. bottom side of main

C. top side of main

D. left side of main

E. right side of main

2244. Volumetric efficiency of a compressor with clearance volume ________________?
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A. decreases with increase in compression ratio

B. may increase/decrease depending on compressor capacity

C. in not dependent upon compression ratio

D. increases with increase in compression ratio

E. unpredictable

2245. Gas turbine cycle with Regenerator __________________?
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A. permits high moisture content fuel to be used

B. decreases heat loss is exhaust

C. allows operation at very high altitudes

D. increases thermal efficiency

E. allows high compression ratio

2246. The area of actual indicator diagram on an air compressor as compared to area of ideal indicator diagram is_____________________?
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A. same

B. less

C. unpredictable

D. more/less depending on compressor capacity

E. more
2247. The capacity of a compressor is 5 m /mih. 5 m /min refers to_______________?
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A. free air

B. air sucked

C. standard air

D. compressed air at delivery pressure

E. compressed air

2248. Pressure ratio in gas turbines is the ratio of ____________________?
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A. inlet pressure to exhaust pressure

B. compressor pressure ratio

C. pressures across the turbine

D. highest pressure to exhaust pressure

E. none of the above

2249. Ratio of indicated H.P. and brake H.P. is known as_________________?
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A. mechanical efficiency

B. relative efficiency

C. adiabatic efficiency

D. isothermal efficiency

E. volumetric efficiency

2250. The closed cycle in gas turbines_________________?
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A. in never used

B. is used when gas is to be burnt

C. provides greater flexibility

D. provides lesser flexibility

E. none of the above