McqMate
These multiple-choice questions (MCQs) are designed to enhance your knowledge and understanding in the following areas: Mechanical Engineering .
| 351. |
The exit velocity in the nozzle increases as per |
| A. | stagnation point |
| B. | continuity equation |
| C. | prandtl number |
| D. | newton’s law |
| Answer» B. continuity equation | |
| 352. |
Compressible flow is a flow that deals with |
| A. | fluid temperature |
| B. | fluid pressure |
| C. | fluid density |
| D. | fluid geometry |
| Answer» C. fluid density | |
| 353. |
The coefficient of kinetic friction is less than the coefficient of static friction. |
| A. | true |
| B. | false |
| Answer» A. true | |
| 354. |
A cubical block rests on an inclined plane of μ = 1/√3, determine the angle of inclination when the block just slides down the inclined plane? |
| A. | 40° |
| B. | 50° |
| C. | 30° |
| D. | 20° |
| Answer» C. 30° | |
| 355. |
When a gas is pushed through a pipe, the gaseous molecules are by the pipe’s walls |
| A. | attracted |
| B. | absorbed |
| C. | deflected |
| D. | dissipated |
| Answer» C. deflected | |
| 356. |
Gas flows through the nozzle from an area of pressure (called the chamber) to one of pressure |
| A. | high, low |
| B. | low, high |
| C. | same, same |
| D. | constant, infinite |
| Answer» A. high, low | |
| 357. |
On what basis are fire and water tube boilers are classified? |
| A. | depending the combustion products formed |
| B. | depending the state of fuel |
| C. | depending on the steam formation rate |
| D. | depending tubular heating surface |
| Answer» D. depending tubular heating surface | |
| 358. |
Stirling boiler is an example of which type of boiler? |
| A. | inclined tube boilers |
| B. | mobile boiler |
| C. | fire tube boiler |
| D. | water tube boiler |
| Answer» D. water tube boiler | |
| 359. |
Which of these is a stationary boiler? |
| A. | locomotive boiler |
| B. | marine boiler |
| C. | mobile boiler |
| D. | babcock-wilcox boiler |
| Answer» D. babcock-wilcox boiler | |
| 360. |
Which of these is a mobile boiler? |
| A. | lancashire boiler |
| B. | stirling boiler |
| C. | locomotive boiler |
| D. | cochran boiler |
| Answer» C. locomotive boiler | |
| 361. |
Are boilers defined on the basis of heat source. |
| A. | yes |
| B. | no |
| Answer» A. yes | |
| 362. |
What is the steam pressure limit of natural circulation boilers? |
| A. | 650bar |
| B. | 180bar |
| C. | 400bar |
| D. | 550bar |
| Answer» B. 180bar | |
| 363. |
Which of the given boilers operate above critical pressure? |
| A. | natural circulation boilers |
| B. | forced circulation boilers |
| C. | once-through boilers |
| D. | water tube boilers |
| Answer» C. once-through boilers | |
| 364. |
Which type of boilers are called drum-less boilers? |
| A. | natural circulation boilers |
| B. | fire tube boilers |
| C. | positive forced circulation boiler |
| D. | forced circulation boiler |
| Answer» C. positive forced circulation boiler | |
| 365. |
Chances of sediments depositing inside the water tubes in the shell is less due to? |
| A. | low working pressure |
| B. | natural circulation of water |
| C. | partial circulation of water |
| D. | high working pressure |
| Answer» D. high working pressure | |
| 366. |
Out of the given option choose the advantage that supports fire tube boilers? |
| A. | water circulation is cyclic |
| B. | used as a mobile boiler |
| C. | water circulation is limited inside boiler shell |
| D. | bursting of flue tube does not cause any explosion |
| Answer» C. water circulation is limited inside boiler shell | |
| 367. |
Tubular air preheater of a boiler is also called as |
| A. | recuperative air preheater |
| B. | elliptical air preheater |
| C. | ovoid air preheater |
| D. | squarish air preheater |
| Answer» A. recuperative air preheater | |
| 368. |
What does regenerative air preheater consists of? |
| A. | rotor |
| B. | skewers |
| C. | propeller |
| D. | piston |
| Answer» A. rotor | |
| 369. |
Which fuel is prepared by moulding finely ground coal under pressure? |
| A. | coke |
| B. | charcoal |
| C. | briquette coal |
| D. | lignite |
| Answer» C. briquette coal | |
| 370. |
Which fuel has the lightest liquid petroleum fraction? |
| A. | diesel |
| B. | petrol |
| C. | distillate |
| D. | kerosene |
| Answer» B. petrol | |
| 371. |
Which statement about impulse turbine is true? |
| A. | steam expands over blades |
| B. | steam expends completely in stationary nozzels |
| C. | steam expends partially over nozzle and turbine blades |
| D. | steam expends over blades incompletely |
| Answer» B. steam expends completely in stationary nozzels | |
| 372. |
In velocity compounding the steam is expanded from the boiler pressure to condenser pressure in one set of stationary blades on nozzle. |
| A. | true |
| B. | false |
| Answer» A. true | |
| 373. |
In condensing turbines vacuum is obtained by |
| A. | sudden pressure drop |
| B. | removal of non condensable gases |
| C. | sudden drop in pressure and by removal of non condensable gases |
| D. | none of the mentioned |
| Answer» C. sudden drop in pressure and by removal of non condensable gases | |
| 374. |
Reaction turbine works with the force obtained from change in pressure energy. |
| A. | true |
| B. | false |
| Answer» A. true | |
| 375. |
A turbine having alternate blades and nozzles is called as |
| A. | impulse turbine |
| B. | reaction turbine |
| C. | impulse & reaction turbine |
| D. | none of the mentioned |
| Answer» A. impulse turbine | |
| 376. |
Compounding efficiency at low speed. |
| A. | decrease |
| B. | increase |
| C. | maximizes |
| D. | none of the mentioned |
| Answer» B. increase | |
| 377. |
In pressure compounded turbines moving nozzles are followed by turbine blades. |
| A. | true |
| B. | false |
| Answer» B. false | |
| 378. |
In pressure compounded turbines flow passage is from |
| A. | moving nozzles to fixed blades |
| B. | fixed nozzles to moving blades |
| C. | fixed blades to moving nozzles |
| D. | none of the mentioned |
| Answer» B. fixed nozzles to moving blades | |
| 379. |
A plant producing both, electrical power & process heat simultaneously is? |
| A. | cogenital plant |
| B. | cogenerial plant |
| C. | cogeneration plant |
| D. | conglomerate plant |
| Answer» C. cogeneration plant | |
| 380. |
In a by-product power cycle? |
| A. | the power is produced initially |
| B. | power production is in the middle stages of the cycle |
| C. | power production is after the cycle has ended |
| D. | none of the mentioned |
| Answer» C. power production is after the cycle has ended | |
| 381. |
In terms of cost per MW compared to condensing sets of the same power, the back pressure turbines are? |
| A. | more expensive |
| B. | cheaper |
| C. | costly |
| D. | none of the mentioned |
| Answer» B. cheaper | |
| 382. |
Which of the following is a good medium for constant temperature heating? |
| A. | water |
| B. | steam |
| C. | coolant |
| D. | diesel |
| Answer» B. steam | |
| 383. |
The cogeneration plant efficiency nCO if WT, Qi, QH represents turbine work, heat input, heat output respectively is given by? |
| A. | nco = (wt + qi) / qh |
| B. | nco = (wt – qi) / qh |
| C. | nco = (wt + qh) / qi |
| D. | nco = (wt + qh) / qi |
| Answer» D. nco = (wt + qh) / qi | |
| 384. |
If e is the electricity fraction of the total energy output, m is the electric plant efficiency and n is the steam generator efficiency; the heat added per unit total energy output is given by? |
| A. | (1 / m) + ((1 – e) / n) |
| B. | (1 / n) + ((1 – e) / m) |
| C. | (1 / m) + ((1 + e) / n) |
| D. | (1 / n) + ((1 – e) / m) |
| Answer» A. (1 / m) + ((1 – e) / n) | |
| 385. |
Which of these is not considered economical for cogeneration? |
| A. | a high fraction of electric to total energy |
| B. | a low fraction of electric to total energy |
| C. | a low fraction of total energy to electric energy |
| D. | none of the mentioned |
| Answer» B. a low fraction of electric to total energy | |
| 386. |
The energy transfer between the hot fluid and cold fluids is brought about by their complete physical mixing in |
| A. | direct contact heat exchanger |
| B. | regenerators |
| C. | recuperators |
| D. | boilers |
| Answer» A. direct contact heat exchanger | |
| 387. |
In vapour refrigeration cycle, which of the following is used for expansion? |
| A. | expansion engine |
| B. | throttling valve or capillary tube |
| C. | both of the mentioned |
| D. | none of the mentioned |
| Answer» B. throttling valve or capillary tube | |
| 388. |
Wet compression is preferred over dry compression. |
| A. | true |
| B. | false |
| C. | topic 5.1 vapour compression refrigeration cycle, effect of superheat and sub-cooling, performance calculations |
| Answer» B. false | |
| 389. |
One tonne of refrigeration is given as the rate of heat removal from surroundings equivalent to heat required for melting one tonne of ice in a day. |
| A. | true |
| B. | false |
| Answer» A. true | |
| 390. |
Superheating of vapour and subcooling of liquid the refrigerating effect. |
| A. | decreases |
| B. | increases |
| C. | no change |
| D. | none of the mentioned |
| Answer» B. increases | |
| 391. |
A condenser must and then the compressed refrigerant. |
| A. | superheat, evaporate |
| B. | desuperheat, evaporate |
| C. | superheat, condense |
| D. | desuperheat, condense |
| Answer» D. desuperheat, condense | |
| 392. |
The vapour going to condenser is in temperature and in ammonia. |
| A. | higher, less |
| B. | higher, richer |
| C. | lower, less |
| D. | lower, richer |
| Answer» D. lower, richer | |
| 393. |
Water is used as a in air conditioning units. |
| A. | absorbent |
| B. | refrigerant |
| C. | absorbent and refrigerant |
| D. | none of the mentioned |
| Answer» B. refrigerant | |
| 394. |
Which of the following types of filters used in the air conditioning system is made of cloth that is discarded on getting dirty? |
| A. | viscous type filters |
| B. | dry filter |
| C. | spray washers |
| D. | electric precipitators |
| Answer» B. dry filter | |
| 395. |
Select the disadvantage of cooling pond out of the given? |
| A. | the area required of cooling in a cooling pond is small |
| B. | spray losses due to evaporation and windage run high |
| C. | there is no control over the temperature of cooled water |
| D. | the cooling efficiency is low compared with cooling water |
| Answer» C. there is no control over the temperature of cooled water | |
| 396. |
How is water circulated throughout the dry cooling tower system? |
| A. | finned tubes |
| B. | metal pipes |
| C. | porous tubes |
| D. | swirling tubes |
| Answer» A. finned tubes | |
Done Studing? Take A Test.
Great job completing your study session! Now it's time to put your knowledge to the test. Challenge yourself, see how much you've learned, and identify areas for improvement. Don’t worry, this is all part of the journey to mastery. Ready for the next step? Take a quiz to solidify what you've just studied.