McqMate
Chapters
| 301. |
The whirl velocity at inlet of a Kaplan turbine is 7.5 m/s and blade velocity is 5 m/s. The volume flow rate of water in 20 m3/s. Find the power output available at the shaft if the mechanical efficiency is 93% (in MW)? |
| A. | 0.831 |
| B. | 0.697 |
| C. | 1.362 |
| D. | 0.298 |
| Answer» B. 0.697 | |
| 302. |
In a Kaplan Turbine experimental setup, the power output of the shaft is 4.325 MW. The volume flow rate of water in 15 m3/s at an available head of 50 m. Find the overall efficiency of the turbine in % (g = 10 m/s2)? |
| A. | 57.66 |
| B. | 83.63 |
| C. | 81.33 |
| D. | 79.95 |
| Answer» A. 57.66 | |
| 303. |
The hydraulic efficiency of a Kaplan turbine is 95%, the mechanical efficiency is 93% and the volumetric efficiency is assumed to be 100%. Fine the overall efficiency (in %)? |
| A. | 80.05 |
| B. | 93.15 |
| C. | 87.55 |
| D. | 88.35 |
| Answer» D. 88.35 | |
| 304. |
Which of the following efficiencies for Kaplan Turbine is defined as the ratio between the power available at the shaft to the power supplied by water at the inlet? |
| A. | Hydraulic efficiency |
| B. | Volumetric efficiency |
| C. | Mechanical efficiency |
| D. | Overall efficiency |
| Answer» D. Overall efficiency | |
| 305. |
In Kaplan turbine apparatus, the volume flow rate of water in 15 m3/s at an available head of 55 m (g = 10 m/s2). Find the shaft power (in MW) if the overall efficiency of the turbine is 95%. |
| A. | 78.3 |
| B. | 7.83 |
| C. | 783 |
| D. | 0.783 |
| Answer» B. 7.83 | |
| 306. |
Draft tube is also called |
| A. | Straight divergent tube |
| B. | Simple elbow tube |
| C. | Thermal tube |
| D. | Elbow tube with varying cross section |
| Answer» A. Straight divergent tube | |
| 307. |
A draft tube helps in converting kinetic energy into |
| A. | Electrical work |
| B. | Mechanical work |
| C. | Chemical work |
| D. | Thermal work |
| Answer» B. Mechanical work | |
| 308. |
Most common application of the draft tube is |
| A. | Rotor |
| B. | Motor |
| C. | Pump |
| D. | Filter |
| Answer» C. Pump | |
| 309. |
Draft tube consists of conical diffuser with angles of |
| A. | 10 deg |
| B. | 20 deg |
| C. | 30 deg |
| D. | 40 deg |
| Answer» A. 10 deg | |
| 310. |
What is the purpose of a Draft tube? |
| A. | To prevent flow separation |
| B. | To avoid Pressure drag |
| C. | To prevent rejection of heat |
| D. | To increase efficiency |
| Answer» A. To prevent flow separation | |
| 311. |
What is the maximum value of efficiency in a draft tube? |
| A. | 100 |
| B. | 50 |
| C. | 90 |
| D. | 40 |
| Answer» C. 90 | |
| 312. |
Turbine that consists of draft tubes is called as_ |
| A. | Impulse turbine |
| B. | Curtis turbine |
| C. | Rateau turbine |
| D. | Reaction turbine |
| Answer» D. Reaction turbine | |
| 313. |
Which of the following is a 50 percent reaction turbine? |
| A. | Parsons turbine |
| B. | Curtis turbine |
| C. | Rateau turbine |
| D. | Pelton wheel |
| Answer» A. Parsons turbine | |
| 314. |
The simple elbow draft tube helps to cut down the cost of excavation. |
| A. | True |
| B. | False |
| C. | none |
| D. | none |
| Answer» A. True | |
| 315. |
The exit diameter for a simple elbow draft tube should be |
| A. | Large |
| B. | Small |
| C. | Very small |
| D. | Same |
| Answer» A. Large | |
| 316. |
Properties that do not affect a draft tube is |
| A. | Pressure |
| B. | Temperature |
| C. | Pressure velocity |
| D. | Velocity |
| Answer» B. Temperature | |
| 317. |
The other name for elbow with varying cross section tube is called |
| A. | Pressure tube |
| B. | Bent draft tube |
| C. | Velocity tube |
| D. | Sink tube |
| Answer» B. Bent draft tube | |
| 318. |
What is the efficiency of the simple elbow type draft tube? |
| A. | 10 |
| B. | 30 |
| C. | 60 |
| D. | 90 |
| Answer» C. 60 | |
| 319. |
The horizontal portion of the draft tube is usually bent to prevent entry of air from the exit end. |
| A. | True |
| B. | False |
| C. | none |
| D. | none |
| Answer» A. True | |
| 320. |
The efficiency of the draft tube is ratio of |
| A. | Pressure energy by kinetic energy |
| B. | Kinetic energy by Pressure energy |
| C. | Kinetic energy into mechanical energy |
| D. | Pressure into mechanical |
| Answer» B. Kinetic energy by Pressure energy | |
| 321. |
Draft tubes are not used in which of the following turbines? |
| A. | Francis |
| B. | Reaction |
| C. | Kaplan |
| D. | Pelton |
| Answer» D. Pelton | |
| 322. |
The draft tube at the exit of the nozzle increases the |
| A. | Temperature |
| B. | Pressure |
| C. | Volume of the flow |
| D. | Density of flow |
| Answer» B. Pressure | |
| 323. |
Efficiency of a draft tube gives |
| A. | Temperature difference |
| B. | Pressure difference |
| C. | Kinetic energy difference |
| D. | Density of flow |
| Answer» C. Kinetic energy difference | |
| 324. |
Cavitation in a draft tube occurs when |
| A. | Temperature difference |
| B. | Pressure drop |
| C. | Kinetic energy difference |
| D. | Density of flow |
| Answer» B. Pressure drop | |
| 325. |
Which among the following is an important parameter to avoid cavitation? |
| A. | Tail race length |
| B. | Head race length |
| C. | Height of draft tube |
| D. | Pump |
| Answer» C. Height of draft tube | |
| 326. |
The draft tube is situated in the |
| A. | Inlet |
| B. | Outlet |
| C. | Tank |
| D. | Nozzle |
| Answer» B. Outlet | |
| 327. |
Which equation is applied to determine the flow? |
| A. | Newtons equation |
| B. | Rutherford’s equation |
| C. | Bernoulli’s equation |
| D. | Faradays equation |
| Answer» C. Bernoulli’s equation | |
| 328. |
Height of the draft tube is denoted by |
| A. | H |
| B. | h |
| C. | z |
| D. | x |
| Answer» C. z | |
| 329. |
Draft tube allows turbine to be placed above the tail race. |
| A. | True |
| B. | False |
| C. | none |
| D. | none |
| Answer» A. True | |
| 330. |
The efficiency of the draft tube depends on the |
| A. | Heat |
| B. | Pressure |
| C. | Temperature |
| D. | Pressure and temperature |
| Answer» D. Pressure and temperature | |
| 331. |
Draft tubes have shafts |
| A. | Horizontal |
| B. | Vertical |
| C. | Circular |
| D. | Cross sectional |
| Answer» B. Vertical | |
| 332. |
Draft tubes are situated at the outlet in |
| A. | Pelton |
| B. | Reaction |
| C. | Kaplan |
| D. | Francis |
| Answer» A. Pelton | |
| 333. |
Efficiency of a draft tube is directly proportional to its |
| A. | Temperature |
| B. | Pressure |
| C. | Velocity |
| D. | Density |
| Answer» C. Velocity | |
| 334. |
Z is a draft tube is |
| A. | Temperature difference |
| B. | Pressure drop |
| C. | Kinetic energy difference |
| D. | Datum head |
| Answer» D. Datum head | |
| 335. |
Draft tube operates at |
| A. | Same efficiency |
| B. | Different efficiency |
| C. | Turbine |
| D. | Pump |
| Answer» A. Same efficiency | |
| 336. |
The draft tube is an |
| A. | Interior tube |
| B. | Exterior tube |
| C. | Tank depth alternator |
| D. | Nozzle tube |
| Answer» B. Exterior tube | |
| 337. |
What type of pressure does the draft tube depend upon? |
| A. | Gauge pressure |
| B. | Atm pressure |
| C. | Normal pressure |
| D. | Normal and Atm pressure |
| Answer» A. Gauge pressure | |
| 338. |
Gauge pressure of the draft tube is denoted by |
| A. | P |
| B. | h |
| C. | z |
| D. | x |
| Answer» A. P | |
| 339. |
Draft tube allows turbine to be placed below the tail race. |
| A. | True |
| B. | False |
| C. | none |
| D. | none |
| Answer» B. False | |
| 340. |
Specific speed is denoted by |
| A. | N |
| B. | n |
| C. | Ns |
| D. | S |
| Answer» C. Ns | |
| 341. |
Specific speeds are used in pumps to determine |
| A. | Temperature |
| B. | Reaction speed |
| C. | Suction specific speed |
| D. | Wheel speed |
| Answer» C. Suction specific speed | |
| 342. |
The tube at the exit of the nozzle increases the |
| A. | Temperature |
| B. | Pressure |
| C. | Volume of the flow |
| D. | Density of flow |
| Answer» B. Pressure | |
| 343. |
Specific speed is used to characterize |
| A. | Turbomachinery speed |
| B. | Flow speed |
| C. | Energy flow |
| D. | Heat generated |
| Answer» A. Turbomachinery speed | |
| 344. |
Specific speed predicts the shape of a/an |
| A. | Pump |
| B. | Density head |
| C. | Impeller |
| D. | Motor |
| Answer» C. Impeller | |
| 345. |
What helps in categorizing the impellers? |
| A. | Quasi static number |
| B. | Rotor |
| C. | Height of draft tube |
| D. | Pump |
| Answer» A. Quasi static number | |
| 346. |
Imperial units is defined as |
| A. | Temperature by pressure |
| B. | Tail race and head race |
| C. | Revolutions per minute |
| D. | Turbine performance |
| Answer» C. Revolutions per minute | |
| 347. |
Ratio of pump or turbine with reference pump or turbine is called as |
| A. | Efficiency |
| B. | Performance |
| C. | Heat generated |
| D. | Relative velocity |
| Answer» B. Performance | |
| 348. |
Low specific speed in hydraulic head is developed due to |
| A. | Mass flow rate |
| B. | Increase in temperature |
| C. | Centrifugal force |
| D. | Increase in pressure |
| Answer» C. Centrifugal force | |
| 349. |
Centrifugal pump impellers have speed ranging from |
| A. | 500- 10000 |
| B. | 50- 100 |
| C. | 200-300 |
| D. | 0-50 |
| Answer» A. 500- 10000 | |
| 350. |
What is the unit of specific speed in metric system? |
| A. | m.s |
| B. | m/s |
| C. | m3/s |
| D. | m |
| Answer» C. m3/s | |
| 351. |
Specific speed develop a hydraulic flow through the centrifugal pumps. |
| A. | True |
| B. | False |
| C. | none |
| D. | none |
| Answer» A. True | |
| 352. |
Net suction speed is used in problems with cavitation. |
| A. | True |
| B. | False |
| C. | none |
| D. | none |
| Answer» A. True | |
| 353. |
The runner diameter in a turbine is denoted as |
| A. | A |
| B. | Dr |
| C. | Rr |
| D. | De |
| Answer» D. De | |
| 354. |
Specific speed is the speed of the turbine which is similar to its |
| A. | Temperature difference |
| B. | Pressure difference |
| C. | Aspect ratio |
| D. | Speed of rotor |
| Answer» C. Aspect ratio | |
| 355. |
Specific speed develops a unit power under a unit |
| A. | Temperature |
| B. | Pressure |
| C. | Volume of the flow |
| D. | Head |
| Answer» D. Head | |
| 356. |
Impeller in a motor is used to |
| A. | Change temperatures |
| B. | Change Pressure |
| C. | Kinetic energy change |
| D. | Change density |
| Answer» B. Change Pressure | |
| 357. |
Hydraulic head is also called as |
| A. | Pressure head |
| B. | Density head |
| C. | Kinetic head |
| D. | Piezometric head |
| Answer» D. Piezometric head | |
| 358. |
Specific speed of a Pelton wheel with single jet is |
| A. | 8.5 to 30 |
| B. | 30 to 51 |
| C. | 51 to 225 |
| D. | 230 to 500 |
| Answer» A. 8.5 to 30 | |
| 359. |
Specific speed is an index used to predict |
| A. | Head race distance |
| B. | Tail race distance |
| C. | Tank dimensions |
| D. | Turbine performance |
| Answer» D. Turbine performance | |
| 360. |
Specific speed of a Pelton wheel with multiple jets is |
| A. | 8.5 to 30 |
| B. | 30 to 51 |
| C. | 51 to 225 |
| D. | 230 to 500 |
| Answer» B. 30 to 51 | |
| 361. |
Specific speed of a Francis turbine is |
| A. | 8.5 to 30 |
| B. | 30 to 51 |
| C. | 51 to 225 |
| D. | 230 to 500 |
| Answer» C. 51 to 225 | |
| 362. |
Specific speed of a Kaplan turbine is |
| A. | 8.5 to 30 |
| B. | 30 to 51 |
| C. | 51 to 225 |
| D. | 355 to 860 |
| Answer» D. 355 to 860 | |
| 363. |
Specific speed less than 500 are called |
| A. | Positive displacement pumps |
| B. | Negative displacement pumps |
| C. | Draft tubes |
| D. | Tanks |
| Answer» A. Positive displacement pumps | |
| 364. |
With the increase in specific speeds, |
| A. | Head race distance increases |
| B. | Tail race distance increases |
| C. | Tank dimensions increases |
| D. | Diameters of impeller increases |
| Answer» D. Diameters of impeller increases | |
| 365. |
Specific speed is used to predict desired pump or turbine performance. |
| A. | True |
| B. | False |
| C. | none |
| D. | none |
| Answer» A. True | |
| 366. |
Once we know the desired functions of the specific speed, it is easier to calculate its components units. |
| A. | True |
| B. | False |
| C. | none |
| D. | none |
| Answer» A. True | |
| 367. |
Which among the following is not a unit quantity of turbine? |
| A. | Unit speed |
| B. | Unit discharge |
| C. | Unit power |
| D. | Unit temperature |
| Answer» D. Unit temperature | |
| 368. |
What does DMU stand for? |
| A. | Density matter usage |
| B. | Direct material usage |
| C. | Density material usage |
| D. | Depth matter usage |
| Answer» B. Direct material usage | |
| 369. |
Unit speed is the speed of the turbine operating under_ |
| A. | One-meter head |
| B. | Pressure head |
| C. | Volumetric head |
| D. | Draft tube |
| Answer» A. One-meter head | |
| 370. |
One dyne is equal to N. |
| A. | 10 |
| B. | 100 |
| C. | 1000 |
| D. | 10-5 |
| Answer» D. 10-5 | |
| 371. |
What is symbol for unit speed? |
| A. | S |
| B. | N |
| C. | Ns |
| D. | Nu |
| Answer» D. Nu | |
| 372. |
Unit speed of a single jet in a turbine is |
| A. | 100 m/s |
| B. | 300 m/s |
| C. | 500 m/s |
| D. | 800 m/s |
| Answer» D. 800 m/s | |
| 373. |
Unit speed is directly proportional to |
| A. | Head race distance |
| B. | Specific speed |
| C. | Pressure |
| D. | Turbine performance |
| Answer» B. Specific speed | |
| 374. |
Unit discharge is the discharge through the turbine when the head of the turbine is |
| A. | High |
| B. | Zero |
| C. | Unity |
| D. | Low |
| Answer» C. Unity | |
| 375. |
9 Unit discharge is denoted as |
| A. | Du |
| B. | Qu |
| C. | Su |
| D. | Nu |
| Answer» B. Qu | |
| 376. |
Unit discharge is directly proportional to |
| A. | Head race distance |
| B. | Discharge of fluid in the turbine. |
| C. | Pressure |
| D. | Turbine performance |
| Answer» B. Discharge of fluid in the turbine. | |
| 377. |
Unit quantities are physical quantities |
| A. | With numerical variables |
| B. | Without numerical variables |
| C. | With different sets |
| D. | With unit difference |
| Answer» B. Without numerical variables | |
| 378. |
Dyne cm is a Torque measurement unit. |
| A. | True |
| B. | False |
| C. | none |
| D. | none |
| Answer» A. True | |
| 379. |
Unit quantities play an important role in determining the dimensional quantities. |
| A. | True |
| B. | False |
| C. | none |
| D. | none |
| Answer» A. True | |
| 380. |
Unit power is developed by the turbine when the head of the turbine is unity. |
| A. | True |
| B. | False |
| C. | none |
| D. | none |
| Answer» A. True | |
| 381. |
Constant head curves are also called as |
| A. | Head race curves |
| B. | Tail race curves |
| C. | Main characteristic curves |
| D. | Impeller curves |
| Answer» C. Main characteristic curves | |
| 382. |
The speed of the turbine in a constant head curve is varied by |
| A. | Temperature change |
| B. | Reaction speed change |
| C. | Changing the gate opening |
| D. | Wheel speed change |
| Answer» C. Changing the gate opening | |
| 383. |
Constant speed curves travel at constant speed when the value is equal to |
| A. | 0 |
| B. | 1 |
| C. | 2 |
| D. | 3 |
| Answer» B. 1 | |
| 384. |
Power of a turbine is measured |
| A. | Mechanically |
| B. | Electrically |
| C. | Chemically |
| D. | Thermally |
| Answer» A. Mechanically | |
| 385. |
Which among the following is not a parameter to determine the efficiency of the turbine? |
| A. | Unit speed |
| B. | Unit power |
| C. | Unit volume |
| D. | Unit discharge |
| Answer» C. Unit volume | |
| 386. |
Which among the following is not an important parameter to determine the performance of the turbine? |
| A. | Speed |
| B. | Discharge |
| C. | Head |
| D. | Volume of tank |
| Answer» D. Volume of tank | |
| 387. |
Which among the following is not a type of curve? |
| A. | Logarithimic curve |
| B. | Straight curve |
| C. | Pressure vs power |
| D. | Efficiency vs speed |
| Answer» C. Pressure vs power | |
| 388. |
The inlet passage of water entry is controlled by |
| A. | Head race |
| B. | Gate |
| C. | Tail race |
| D. | Pump |
| Answer» B. Gate | |
| 389. |
Overall efficiency vs what is drawn to determine the turbine performance? |
| A. | Unit Discharge |
| B. | Unit speed |
| C. | Unit power |
| D. | Unit pressure |
| Answer» B. Unit speed | |
| 390. |
Constant discharge takes place due to |
| A. | Unit Discharge |
| B. | Unit speed |
| C. | Unit power |
| D. | Unit pressure |
| Answer» B. Unit speed | |
| 391. |
All the characteristic curves are drawn with respect to |
| A. | Unit Discharge |
| B. | Unit speed |
| C. | Unit power |
| D. | Unit pressure |
| Answer» B. Unit speed | |
| 392. |
In constant speed curves, the speed is kept a constant varying its head. |
| A. | True |
| B. | False |
| C. | none |
| D. | none |
| Answer» A. True | |
| 393. |
In all the characteristic curves, the overall efficiency is aimed at the maximum value. |
| A. | True |
| B. | False |
| C. | none |
| D. | none |
| Answer» A. True | |
| 394. |
Constant efficiency curves are plotted using |
| A. | Constant head curves |
| B. | Constant speed curves |
| C. | Main characteristic curves |
| D. | Constant speed and constant head |
| Answer» D. Constant speed and constant head | |
| 395. |
Constant speed curves are also called as |
| A. | Main characteristic curves |
| B. | Turbine curves |
| C. | Tail race curves |
| D. | Impeller curves |
| Answer» C. Tail race curves | |
| 396. |
Constant speed curve is denoted as |
| A. | T |
| B. | V |
| C. | c |
| D. | V |
| Answer» C. c | |
| 397. |
Constant speed curves are |
| A. | Scalar quantities |
| B. | Vector quantities |
| C. | Constant quantities |
| D. | Different conditions |
| Answer» B. Vector quantities | |
| 398. |
Constant speed is measured |
| A. | Mechanically |
| B. | Electrically |
| C. | Chemically |
| D. | Thermally |
| Answer» A. Mechanically | |
| 399. |
Constant speed curves are determined by the |
| A. | Arc length |
| B. | Power |
| C. | Heat |
| D. | Temperature |
| Answer» C. Heat | |
| 400. |
Which component is necessary for writing the velocity equation? |
| A. | Cos component |
| B. | Sine Component |
| C. | Cos and sine component |
| D. | Independent |
| Answer» C. Cos and sine component | |
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