MCQOPTIONS
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MCQOPTIONS
This section includes 463 Mcqs, each offering curated multiple-choice questions to sharpen your Mechanical Engineering knowledge and support exam preparation. Choose a topic below to get started.
| 301. |
Resistance of water dominating the steam is called as _______ |
| A. | hydraulic water hammer |
| B. | erosion |
| C. | contamination |
| D. | none of the mentioned |
| Answer» C. contamination | |
| 302. |
After steam bubbles break the water surface, they carry water droplets this is called as ________ |
| A. | entrainment |
| B. | capillarity |
| C. | reverse capillarity |
| D. | none of the mentioned |
| Answer» B. capillarity | |
| 303. |
If heat is added to the wet steam temperature _________ |
| A. | raises immediately |
| B. | decreases immediately |
| C. | raises after sometime |
| D. | none of the mentioned |
| Answer» D. none of the mentioned | |
| 304. |
Entrainment happens at __________ |
| A. | liquid surface having contact with atmosphere |
| B. | outlet of the boiler |
| C. | inlet of the boiler |
| D. | none of the mentioned |
| Answer» C. inlet of the boiler | |
| 305. |
Supersaturated steam is also called as _________ |
| A. | saturated steam |
| B. | single phase mix |
| C. | two phase mix |
| D. | none of the mentioned |
| Answer» D. none of the mentioned | |
| 306. |
Mixture of steam and liquid water is called as _________ |
| A. | dry steam |
| B. | wet steam |
| C. | saturated steam |
| D. | none of the mentioned |
| Answer» C. saturated steam | |
| 307. |
Shock wave causes instantaneous _________ to the subsonic speed. |
| A. | increase |
| B. | decrease |
| C. | remains constant |
| D. | none of the mentioned |
| Answer» C. remains constant | |
| 308. |
When flow converts from supersonic to subsonic then __________ is produced. |
| A. | shock wave |
| B. | pressure drop |
| C. | shock wave & pressure drop |
| D. | none of the mentioned |
| Answer» B. pressure drop | |
| 309. |
At vena contracta the velocity is _________ and pressure is ___________ |
| A. | lowest, highest |
| B. | highest, highest |
| C. | highest, lowest |
| D. | none of the mentioned |
| Answer» D. none of the mentioned | |
| 310. |
Head loss in nozzles occurs due to __________ |
| A. | pipes head loss |
| B. | pressure loss |
| C. | friction loss |
| D. | none of the mentioned |
| Answer» B. pressure loss | |
| 311. |
Pressure loss occurs in nozzle due to __________ |
| A. | due to viscous force |
| B. | when fluid flows from convergent to divergent |
| C. | frictional forces |
| D. | none of the mentioned |
| Answer» D. none of the mentioned | |
| 312. |
Coefficient of contraction is the__________ |
| A. | ratio of actual cross sectional area to geometric cross sectional area |
| B. | ratio of geometric cross sectional area to actual cross sectional area |
| C. | ratio of pressure exerted to cross sectional area |
| D. | none of the mentioned |
| Answer» B. ratio of geometric cross sectional area to actual cross sectional area | |
| 313. |
Coefficient of velocity of nozzle is _______________ |
| A. | theoretical velocity/actual velocity |
| B. | actual velocity/theoretical velocity |
| C. | it is an experimental value |
| D. | none of the mentioned |
| Answer» C. it is an experimental value | |
| 314. |
Coefficient of discharge of Nozzle is _______ |
| A. | cd = cc/cv |
| B. | cd = cc*cv |
| C. | cd = cv/cc |
| D. | none of the mentioned |
| Answer» C. cd = cv/cc | |
| 315. |
Critical pressure ratio is ratios of pressures at _________ discharge. |
| A. | minimum |
| B. | none of the mentioned |
| C. | optimum |
| D. | maximum |
| Answer» E. | |
| 316. |
Gas turbines operate at pressures ________ than critical pressure ratio. |
| A. | higher |
| B. | lesser |
| C. | does not depend on pressure ratio |
| D. | none of the mentioned |
| Answer» C. does not depend on pressure ratio | |
| 317. |
Aeroderivative engines are used where ____________ power units are required. |
| A. | larger |
| B. | smaller |
| C. | optimum |
| D. | none of the mentioned |
| Answer» C. optimum | |
| 318. |
Aeroderivative engines have pressure ratios ___________ |
| A. | greater than 30 |
| B. | lesser than 30 and greater than 20 |
| C. | greater than 50 |
| D. | none of the mentioned |
| Answer» B. lesser than 30 and greater than 20 | |
| 319. |
Pressure ratios below 20 are used in _____________ engines. |
| A. | steam turbine |
| B. | aero derivative engines |
| C. | heavy frame engines |
| D. | none of the mentioned |
| Answer» D. none of the mentioned | |
| 320. |
In rocket engines the amount of expansion in Nozzle determines the __________ |
| A. | exit temperature |
| B. | exit pressure |
| C. | exit temperature & pressure |
| D. | none of the mentioned |
| Answer» D. none of the mentioned | |
| 321. |
When mach number is greater than one the flow is ________ |
| A. | subsonic |
| B. | supersonic |
| C. | laminar |
| D. | none of the mentioned |
| Answer» C. laminar | |
| 322. |
In rocket engine the flow in the throat of the nozzle is __________ |
| A. | subsonic |
| B. | laminar |
| C. | turbulent |
| D. | none of the mentioned |
| Answer» B. laminar | |
| 323. |
If mach number is less than one then its flow is ______________ |
| A. | subsonic flow |
| B. | turbulent flow |
| C. | laminar flow |
| D. | none of the mentioned |
| Answer» B. turbulent flow | |
| 324. |
Nozzles used in blast furnaces are called as _______ |
| A. | jet |
| B. | hot blast |
| C. | tuyeres |
| D. | none of the mentioned |
| Answer» D. none of the mentioned | |
| 325. |
Nozzle used in rocket engine is __________ |
| A. | convergent nozzle |
| B. | divergent nozzle |
| C. | convergent – divergent nozzle |
| D. | none of the mentioned |
| Answer» D. none of the mentioned | |
| 326. |
In fountains the type of nozzle used is _______ |
| A. | none of the mentioned |
| B. | turbulent jet |
| C. | high speed nozzle |
| D. | laminar jet |
| Answer» E. | |
| 327. |
A nozzle used to send fluid in coherent stream is called as ________ |
| A. | jet |
| B. | high velocity nozzle |
| C. | every nozzle sends fluid in coherent stream |
| D. | none of the mentioned |
| Answer» B. high velocity nozzle | |
| 328. |
Nozzles are used to control the ___________ |
| A. | temperature |
| B. | rate of flow |
| C. | mass flow rate |
| D. | none of the mentioned |
| Answer» C. mass flow rate | |
| 329. |
Why is induced draught considered better than the forced draught? |
| A. | because power requirement is high for forced draught |
| B. | maintenance of induced draught fan is costlier |
| C. | forced draught is less efficient |
| D. | forced draught produces less amount of speed of air |
| Answer» B. maintenance of induced draught fan is costlier | |
| 330. |
How is air produced in mechanical draught cooling tower? |
| A. | air tuyeres |
| B. | propeller fans |
| C. | air blowers |
| D. | louvre |
| Answer» C. air blowers | |
| 331. |
In which system is Cooling of hot water is done on tray as step by? |
| A. | mechanical draught cooling system |
| B. | hyperbolic cooling tower |
| C. | atmospheric cooling tower |
| D. | wet cooling tower |
| Answer» D. wet cooling tower | |
| 332. |
Why is exhaust steam coming out of turbine is admitted to a steam header? |
| A. | to increase the pressure |
| B. | to decrease the velocity |
| C. | to decrease the pressure drop |
| D. | to control the pollution |
| Answer» D. to control the pollution | |
| 333. |
How does outside air enter into the wet cooling system? |
| A. | air vents |
| B. | louvers |
| C. | tuyeres |
| D. | vacuum |
| Answer» C. tuyeres | |
| 334. |
What type of cooling system is used in the large power plants? |
| A. | cooling ponds |
| B. | natural flow system |
| C. | cooling towers |
| D. | single deck system |
| Answer» D. single deck system | |
| 335. |
What are used in the direct flow system to transverse the pond before uniting at intake? |
| A. | separators |
| B. | filters |
| C. | baffle walls |
| D. | porous pipes |
| Answer» D. porous pipes | |
| 336. |
In which type of cooling system are nozzles arranged on different elevation? |
| A. | single deck system |
| B. | double deck system |
| C. | natural flow system |
| D. | direct flow system |
| Answer» C. natural flow system | |
| 337. |
Which of the following is the simplest method of cooling the condenser water? |
| A. | spray cooling pond |
| B. | cooling tower |
| C. | indirect air cooling |
| D. | hyperbolic cooling tower |
| Answer» B. cooling tower | |
| 338. |
How many number of spray nozzle does each module on spray pond cooling system contains? |
| A. | 1 |
| B. | 2 |
| C. | 3 |
| D. | 4 |
| Answer» E. | |
| 339. |
Open cooling system is also called as |
| A. | parallel system |
| B. | once through system |
| C. | air based system |
| D. | non-reversible system |
| Answer» C. air based system | |
| 340. |
Which of the following is capable of absorbing excess moisture from the air? |
| A. | silica gel |
| B. | charcoal |
| C. | salts of calcium or ammonia |
| D. | activated alumina |
| Answer» D. activated alumina | |
| 341. |
The process of extraction of the certain required amount of water from air is known as |
| A. | heating |
| B. | cooling |
| C. | humidification |
| D. | dehumidification |
| Answer» E. | |
| 342. |
Which of the following statements about electric precipitators is false? |
| A. | they are used to remove dust by providing a strong electric field |
| B. | their initial installation cost is high |
| C. | their operational cost is low |
| D. | dust particles get attached to the positive electrode |
| Answer» E. | |
| 343. |
Viscous type filters are made of screens of spilt wire and coated with non-drying viscous oil in order to catch and remove the dust particles from the incoming air. |
| A. | true |
| B. | false |
| Answer» B. false | |
| 344. |
Which of the following qualities is not possessed by the filters in the air conditioning system? |
| A. | they should be capable of removing dust particles from the incoming air |
| B. | they should afford easy cleaning |
| C. | they should offer low frictional resistance to the airflow |
| D. | they should offer high frictional resistance to the airflow |
| Answer» E. | |
| 345. |
In which component of the chilled water system, the return air and the fresh air mixture is filtered? |
| A. | fan coil unit |
| B. | ducting grill |
| C. | compressor |
| D. | evaporator |
| Answer» B. ducting grill | |
| 346. |
In a chilled water system, the refrigerant is used to cool the air directly while in the direct expansion system, a secondary medium like water is used to cool the air. |
| A. | true |
| B. | false |
| Answer» C. | |
| 347. |
Which of the following is not a component of packaged air conditioners? |
| A. | compressor |
| B. | condenser |
| C. | chiller |
| D. | evaporator |
| Answer» D. evaporator | |
| 348. |
Room air conditioners and packaged units are examples of |
| A. | direct expansion systems |
| B. | indirect expansion systems |
| C. | chilled water systems |
| D. | indirect contraction systems |
| Answer» B. indirect expansion systems | |
| 349. |
Water is used as a in air conditioning units. |
| A. | absorbent |
| B. | refrigerant |
| C. | absorbent and refrigerant |
| D. | none of the mentioned |
| Answer» C. absorbent and refrigerant | |
| 350. |
Lithium bromide-water vapour is another absorption refrigeration system. |
| A. | true |
| B. | false |
| Answer» B. false | |