mechanical engineering MCQs – Page 14

Practise multiple-choice questions from mechanical engineering for competitive examinations and subject revision. Review each marked answer and report any item that may be outdated or unclear.

mechanical engineering Mcqs

1. compressors gas turbines and jet engines 2. theory of machines 3. nuclear power plants 4. engineering materials 5. strength of materials mechanical engineering 6. thermodynamics 7. heat transfer 8. i c engines 9. steam boilers engines nozzles and turbines 10. engineering mechanics 11. fluid mechanics mechanical engineering 12. production technology 13. machine design 14. hydraulic machines 15. workshop technology 16. refrigeration and air conditioning

261. The hottest point in a gas turbine is______________________?
0

A. uniformly heated

B. at the base

C. between ~ to i of the blade height

D. in the center

E. at the tip

262. There is a certain pressure ratio (optimum) for a gas turbine at which its thermal efficiency is maximum. With increase in turbine temperature, the value of pressure ratio for the peak efficiency would__________________?
0

A. unpredictable

B. remain same

C. increase

D. decrease

E. none of the above

263. For minimum work in multistage compression, assuming same index of compression in all stages_________________?
0

A. work done in subsequent stages should decrease

B. work done in any stage is no criterion for minimum work but depends on other factors

C. work done in all stages should be equal

D. work done in subsequent stages should increase

E. work done in first stage should be more

264. For small discharge at high pressure, following pump is preferred_____________________?
0

A. centrifugal

B. axial flow

C. mixed flow

D. propeller

E. reciprocating

265. An air compressor may be controlled by____________________?
0

A. any one of the above

B. blow-off control

C. throttle control B. clearance control

D. none of the above

266. To aviod moisture troubles, the compressed air main line should __________________?
0

A. rise gradually towards the point of use

B. drop gradually towards the point of use

C. none of the above

D. be laid exactly horizontally

E. be laid vertically

267. The flow rate in gear pump___________________?
0

A. unpredictable

B. none of the above

C. more or less remains constant with in-crease in pressure

D. decreases with increase in pressure

E. increases with increase in pressure

268. Gas cooled reactor uses following materials as moderator, and coolant____________________?
0

A. heavy water, C02

B. concrete, N2

C. graphite, air

D. lead, H2

E. graphite, C02

269. Turbofan engine employs ____________________ ?
0

A. two or more air streams

B. one air stream

C. solid fuel firing

D. rocket principle for its operation

E. no air stream

270. In a _____________ , both cutting and non-cutting operations are performed at one station of the press in every stroke of the ram?
0

A. compound die

B. simple die

C. progressive die

D. combination die

271. The efficiency and work ratio of a gas turbine plant can be increased by _____________________?
0

A. injecting water in/around combustion chamber

B. all of the above

C. reheating the air after partial expansion in the turbine

D. adding heat exchanger

E. using mulit-stage compressor with mfercooler

272. The closed cycle in gas turbines_________________?
0

A. in never used

B. provides lesser flexibility

C. is used when gas is to be burnt

D. provides greater flexibility

E. none of the above

273. The maximum propulsion efficiency of a turbojet is attained at around following speed __________________?
0

A. 4000 km/hr

B. 550 km/hr

C. 2400km /hr

D. 1700 km/hr

E. 1050km/hr

274. Water is injected in gas turbine cycle to___________________?
0

A. increase efficiency

B. control temperature

C. control fire hazards

D. control output of turbine

E. it is never done

275. During peak load periods, the best method of controlling compressors is___________________?
0

A. constant speed unloader

B. none of the above

C. variable speed

D. relief valve

E. start-stop motor

276. High specific speed of turbine implies it is__________________?
0

A. none of the above

B. Francis turbine

C. impulse turbine

D. any one of the above

E. propeller turbine

277. The pressure ratio in gas turbines is of the order of__________________?
0

A. 4:01

B. 61: 1

C. 9:01

D. 2:l

E. 12:01

278. Pressure intensifier increases the pressure in proportion to____________________?
0

A. square of ratio of diameters

B. inverse ratio of diameters

C. square of inverse ratio of diameters

D. ratio of diameters

E. fourth power of ratio of diameters

279. In gas turbines^ high thermal efficiency is obtained in_________________?
0

A. closed cycle

B. open cycle

C. both of the above

D. closed/open depending on other con-siderations

E. unpredictable

280. Low specific speed of a pump implies it is____________________?
0

A. mixed flow pump

B. axial flow pump

C. none of the above

D. any one of the above

E. centrifugal pump

Previous Next

Showing 261 to 280 of 4266 mcqs