MCQOPTIONS
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MCQOPTIONS
This section includes 564 Mcqs, each offering curated multiple-choice questions to sharpen your Automobile Engineering knowledge and support exam preparation. Choose a topic below to get started.
| 501. |
The fire tubes in a Locomotive boiler has __________ diameter. |
| A. | 4.75 mm |
| B. | 5.47 mm |
| C. | 7.45 mm |
| D. | 47.5 mm |
| Answer» E. | |
| 502. |
The fire tubes in a Cochran boiler usually have _________ diameter. |
| A. | 6.25 mm |
| B. | 62.5 mm |
| C. | 72.5 mm |
| D. | 92.5 mm |
| Answer» C. 72.5 mm | |
| 503. |
The number of water level indicators in a boiler are generally __________ in number. |
| A. | One |
| B. | Two |
| C. | Three |
| D. | Four |
| Answer» C. Three | |
| 504. |
An impulse turbine as compared to a reaction turbine, for a given power has _________ row of blades. |
| A. | Equal |
| B. | Less |
| C. | More |
| D. | None of these |
| Answer» D. None of these | |
| 505. |
The ratio of the clearance volume to the swept volume is called |
| A. | Cut-off ratio |
| B. | Expansion ratio |
| C. | Clearance ratio |
| D. | None of these |
| Answer» D. None of these | |
| 506. |
The ratio of the volume at cut-off to the swept volume is called |
| A. | Cut-off ratio |
| B. | Expansion ratio |
| C. | Clearance ratio |
| D. | None of these |
| Answer» B. Expansion ratio | |
| 507. |
The feed check valve is used in order to |
| A. | Regulate flow of boiler water |
| B. | Check level of water in boiler drum |
| C. | Recirculate unwanted feed water |
| D. | Allow high pressure feed water to flow to drum and not allow reverse flow to take place |
| Answer» E. | |
| 508. |
Fire tube boilers are |
| A. | Internally fired |
| B. | Externally fired |
| C. | Internally as well as externally fired |
| D. | None of these |
| Answer» B. Externally fired | |
| 509. |
Water tube boilers are |
| A. | Internally fired |
| B. | Externally fired |
| C. | Internally as well as externally fired |
| D. | None of these |
| Answer» C. Internally as well as externally fired | |
| 510. |
In a nozzle, whole frictional loss is assumed to occur between |
| A. | Inlet and throat |
| B. | Inlet and outlet |
| C. | Throat and exit |
| D. | All of these |
| Answer» D. All of these | |
| 511. |
In reaction turbines, the axial thrust is due to |
| A. | Pressure drop across the rotor |
| B. | Change in axial velocity |
| C. | Both (A) and (B) |
| D. | None of these |
| Answer» D. None of these | |
| 512. |
Sublimation region is the region where |
| A. | Solid and vapor phases are in equilibrium |
| B. | Solid and liquid phases are in equilibrium |
| C. | Liquid and vapor phases are in equilibrium |
| D. | Solid, liquid and vapor phases are in equilibrium |
| Answer» B. Solid and liquid phases are in equilibrium | |
| 513. |
The diagram factor is the ratio of the |
| A. | Area of the actual indicator diagram to the area of theoretical indicator diagram |
| B. | Actual workdone per stroke to the theoretical workdone per stroke |
| C. | Actual mean effective pressure to the theoretical mean effective pressure |
| D. | Any one of the above |
| Answer» E. | |
| 514. |
The reheat factor is the ratio of the |
| A. | Cumulative heat drop to the isentropic heat drop |
| B. | Isentropic heat drop to the heat supplied |
| C. | Total useful heat drop to the total isentropic heat drop |
| D. | None of the above |
| Answer» B. Isentropic heat drop to the heat supplied | |
| 515. |
Duplex feed pumps are used in small steam boilers. These operate on the principle of |
| A. | Centrifugal pump |
| B. | Axial flow pump |
| C. | Gear pump |
| D. | Reciprocating pump |
| Answer» E. | |
| 516. |
In a boiler, the heat is lost |
| A. | To dry flue gases |
| B. | In moisture present in the fuel |
| C. | To steam formed by combustion of hydrogen per kg of fuel |
| D. | All of the above |
| Answer» E. | |
| 517. |
The friction present between the steam and the nozzle surfaces reduces the heat drop by |
| A. | 10 to 15% |
| B. | 15 to 25% |
| C. | 25 to 40% |
| D. | 40 to 60% |
| Answer» B. 15 to 25% | |
| 518. |
A valve installed between the boiler and the feed pump is |
| A. | Blow off cock |
| B. | Feed check valve |
| C. | Steam stop valve |
| D. | None of these |
| Answer» C. Steam stop valve | |
| 519. |
Which is not correct statement about effect of sulphur in fuel? |
| A. | It has heating value |
| B. | It helps in electrostatic precipitation of ash in flue gases |
| C. | It leads to corrosion of air heaters, ducting, etc. if flue gas exit temperature is low |
| D. | It erodes furnace walls |
| Answer» E. | |
| 520. |
The principal function of a stop valve is to |
| A. | Control the flow of steam from the boiler to the main pipe and to shut off the steam completely when required |
| B. | Empty the boiler when required and to discharge the mud, scale or sediments which are accumulated at the bottom of the boiler |
| C. | Put off fire in the furnace of the boiler when the level of water in the boiler falls to an unsafe limit |
| D. | Increase the temperature of saturated steam without raising its pressure |
| Answer» B. Empty the boiler when required and to discharge the mud, scale or sediments which are accumulated at the bottom of the boiler | |
| 521. |
The best suited coal for chain or traveling grate stoker boiler is |
| A. | Coking coal |
| B. | Non-coking or free burning coal |
| C. | Pulverized coal |
| D. | High sulphur coal |
| Answer» C. Pulverized coal | |
| 522. |
The action of steam in a steam turbine is |
| A. | Static |
| B. | Dynamic |
| C. | Static and dynamic |
| D. | Neither static nor dynamic |
| Answer» C. Static and dynamic | |
| 523. |
Superheating of steam is done at |
| A. | Constant volume |
| B. | Constant temperature |
| C. | Constant pressure |
| D. | Constant entropy |
| Answer» D. Constant entropy | |
| 524. |
Expanding steam to a very low pressure (high vacuum) in steam engines is |
| A. | Desirable |
| B. | Economical |
| C. | Essential |
| D. | Uneconomical |
| Answer» E. | |
| 525. |
In turbines, the fluid undergoes a continuous steady flow process and the speed of flow is |
| A. | Low |
| B. | Very low |
| C. | High |
| D. | Very high |
| Answer» E. | |
| 526. |
The critical pressure ratio for initially superheated steam is __________ as compared to initially dry saturated steam. |
| A. | More |
| B. | Less |
| C. | Same |
| D. | None of these |
| Answer» C. Same | |
| 527. |
The isentropic enthalpy drop in moving blade is two-third of the isentropic enthalpy drop in fixed blades of a turbine. The degree of reaction will be |
| A. | 0.4 |
| B. | 0.56 |
| C. | 0.67 |
| D. | 1.67 |
| Answer» B. 0.56 | |
| 528. |
In a reaction turbine |
| A. | The steam is allowed to expand in the nozzle, where it gives a high velocity before it enters the moving blades |
| B. | The expansion of steam takes place partly in the fixed blades and partly in the moving blades |
| C. | The steam is expanded from a high pressure to a condenser pressure in one or more nozzles |
| D. | The pressure and temperature of steam remains constant |
| Answer» C. The steam is expanded from a high pressure to a condenser pressure in one or more nozzles | |
| 529. |
The blade friction in the impulse turbine reduces the velocity of steam by __________ while it passes over the blades. |
| A. | 10 to 15% |
| B. | 15 to 20% |
| C. | 20 to 30% |
| D. | 30 to 40% |
| Answer» B. 15 to 20% | |
| 530. |
The temperature of flue gases at air heater outlet should be |
| A. | 100°C |
| B. | Above dew point temperature of flue gases |
| C. | Below dew point temperature of flue gases |
| D. | Less than wet bulb temperature of flue gases |
| Answer» C. Below dew point temperature of flue gases | |
| 531. |
A compound steam engine in which piston rods of high pressure and low pressure cylinders ' are attached to two different cranks set at 180° to each other, is called |
| A. | Receiver type compound engine |
| B. | Tandem type compound engine |
| C. | Woolf type compound engine |
| D. | Both (A) and (B) |
| Answer» D. Both (A) and (B) | |
| 532. |
A compound steam engine in which piston rods of high pressure and low pressure cylinders are attached to two different cranks set at 90° to each other, is called |
| A. | Receiver type compound engine |
| B. | Tandem type compound engine |
| C. | Woolf type compound engine |
| D. | Both (A) and (B) |
| Answer» B. Tandem type compound engine | |
| 533. |
In a 50% reaction turbine stage, tangential component of absolute velocity at rotor inlet is 537 m/s and the blade velocity is 454 m/s. The power output in kW of steam will be |
| A. | 260 kW |
| B. | 282 kW |
| C. | 296 kW |
| D. | 302 kW |
| Answer» C. 296 kW | |
| 534. |
A _________ in a boiler is used to put off fire in the furnace of the boiler when the level of water in the boiler falls to an unsafe limit. |
| A. | Blow off cock |
| B. | Fusible plug |
| C. | Stop valve |
| D. | Safety valve |
| Answer» C. Stop valve | |
| 535. |
Gradually increasing temperature of flue gases at inlet to chimney for given steam outputs is an indication of |
| A. | Higher effectiveness of boiler |
| B. | High calorific value coal being burnt |
| C. | Fouling of heat transfer surfaces |
| D. | Raising of steam temperature |
| Answer» D. Raising of steam temperature | |
| 536. |
The mechanical draught _________ with the amount of smoke. |
| A. | Increases |
| B. | Decreases |
| C. | Does not effect |
| D. | None of these |
| Answer» C. Does not effect | |
| 537. |
In a uniflow engine |
| A. | Steam enters and exhausts through the same port |
| B. | Steam enters at one end and exhausts at the centre |
| C. | Steam enters at the centre and exhausts at the other end |
| D. | None of the above |
| Answer» C. Steam enters at the centre and exhausts at the other end | |
| 538. |
The expansion of steam in a nozzle follows |
| A. | Carnot cycle |
| B. | Rankine cycle |
| C. | Joule cycle |
| D. | Stirling cycle |
| Answer» C. Joule cycle | |
| 539. |
A single stage impulse turbine with a diameter of 1.2 m runs at 3000 r.p.m. If the blade speed ratio is 0.42, then the inlet velocity of steam will be |
| A. | 79 m/s |
| B. | 188 m/s |
| C. | 450 m/s |
| D. | 900 m/s |
| Answer» D. 900 m/s | |
| 540. |
Proximate analysis of fuel is determination of percentage of |
| A. | Carbon, hydrogen, nitrogen, sulphur, moisture |
| B. | Fixed carbon, ash, volatile matter, moisture |
| C. | Higher calorific value |
| D. | Lower calorific value |
| Answer» C. Higher calorific value | |
| 541. |
Ultimate analysis of fuel is determination of percentage of |
| A. | Carbon, hydrogen, nitrogen, sulphur, moisture |
| B. | Fixed carbon, ash, volatile matter, moisture |
| C. | Higher calorific value |
| D. | Lower calorific value |
| Answer» B. Fixed carbon, ash, volatile matter, moisture | |
| 542. |
The function of a flywheel is |
| A. | To convert reciprocating motion of the piston into rotary motion |
| B. | To convert rotary motion of the crankshaft into to and fro motion of the valve rod |
| C. | To prevent fluctuation of speed |
| D. | To keep the engine speed uniform at all load conditions |
| Answer» D. To keep the engine speed uniform at all load conditions | |
| 543. |
A device used to put off fire in the furnace of the boiler when the level of water in the boiler falls to an unsafe limit, is called |
| A. | Blow off cock |
| B. | Stop valve |
| C. | Superheater |
| D. | None of these |
| Answer» E. | |
| 544. |
Which of the following boiler is best suited to meet the fluctuating demand of steam ? |
| A. | Locomotive boiler |
| B. | Lancashire boiler |
| C. | Cornish boiler |
| D. | Babcock and Wilcox boiler |
| Answer» B. Lancashire boiler | |
| 545. |
In a boiler, feed water supplied per hour is 205 kg while coal fired per hour is 23 kg. The net enthalpy rise per kg of water is 145 kJ. If the calorific valve of the coal is 2050 kJ/kg, then the boiler efficiency will be |
| A. | 56% |
| B. | 63% |
| C. | 74% |
| D. | 78% |
| Answer» C. 74% | |
| 546. |
In natural circulation steam boilers, the circulation of water is by convection currents which are set up during the heating of water. |
| A. | Correct |
| B. | Incorrect |
| C. | - |
| D. | - |
| Answer» B. Incorrect | |
| 547. |
The pressure of steam in the engine cylinder at the beginning of the stroke is __________ the boiler pressure. |
| A. | equal to |
| B. | less than |
| C. | higher than |
| D. | - |
| Answer» C. higher than | |
| 548. |
The diameter of Cornish boiler varies from |
| A. | 0.5 to 1 m |
| B. | 1 to 2 m |
| C. | 1.25 to 2.5 m |
| D. | 2 to 3 m |
| Answer» C. 1.25 to 2.5 m | |
| 549. |
The fire tubes in a Cochran boiler are |
| A. | horizontal |
| B. | vertical |
| C. | inclined |
| D. | - |
| Answer» B. vertical | |
| 550. |
In a reciprocating steam engine, the heat energy in the steam is converted into mechanical work by the to and fro motion of the piston. |
| A. | Agree |
| B. | Disagree |
| C. | - |
| D. | - |
| Answer» B. Disagree | |