McqMate
These multiple-choice questions (MCQs) are designed to enhance your knowledge and understanding in the following areas: Mechanical Engineering .
| 351. |
Change in internal energy is least during |
| A. | 25 to 30 |
| B. | Constant pressure process |
| C. | Constant volume process |
| D. | Adiabatic process |
| E. | Isothermal process |
| Answer» E. Isothermal process | |
| 352. |
Which of the following is not a petroleum product? |
| A. | Methylated spirit |
| B. | Lubricating oil |
| C. | Kerosene |
| D. | Carbon dioxide |
| E. | Petrol |
| Answer» A. Methylated spirit | |
| 353. |
Thermal efficiency of a standard Otto cycle for a compression ratio 5.5, will be |
| A. | 100% |
| B. | 47.50% |
| C. | 20% |
| D. | 35.40% |
| E. | 50% |
| Answer» E. 50% | |
| 354. |
The calorific value of methane can be determined by |
| A. | Bomb calorimeter |
| B. | Bunsen's calorimeter |
| C. | Orsat's apparatus |
| D. | Exhaust gas calorimeter |
| E. | None of the above |
| Answer» E. None of the above | |
| 355. |
The fact that the product of pressure and volume of a fixed amount of gas is approximately a constant value is known as |
| A. | Charle's law |
| B. | Gay Lusac's law |
| C. | Dalton's law |
| D. | Lewis law |
| E. | None of the above |
| Answer» E. None of the above | |
| 356. |
Air fuel ratio for a jet engine is of the order of |
| A. | 60;1 |
| B. | 15;1 |
| C. | 600;1 |
| D. | 20;1 |
| E. | 10;1 |
| Answer» A. 60;1 | |
| 357. |
A steam nozzle is said to be choked when |
| A. | Pressure at throat is equal to steam supply pressure |
| B. | Throat gets clogged |
| C. | Flow is at maximum value of critical exit pressure |
| D. | Steam flow through nozzle ceases |
| E. | Pressure at throat is less than the exit pressure |
| Answer» E. Pressure at throat is less than the exit pressure | |
| 358. |
In a four stroke cycle the minimum temperature inside the engine cylinder occurs |
| A. | At the end of exhaust stroke |
| B. | At the end of suction stroke |
| C. | At the end of compression stroke |
| D. | At the beginning of exhaust stroke |
| E. | At the beginning of suction stroke |
| Answer» B. At the end of suction stroke | |
| 359. |
According to Charle's law |
| A. | At constant pressure the volume of a gas is proportional to its absolute temperature |
| B. | At constant temperature, pressure is proportional to temperature |
| C. | At constant temperature, pressure of a gas is proportional to its volume |
| D. | At constant volume the absolute pressure is proportional to the temperature |
| E. | None of the above |
| Answer» A. At constant pressure the volume of a gas is proportional to its absolute temperature | |
| 360. |
Prony brakes are used for testing |
| A. | Slow speed engines |
| B. | High speed engines |
| C. | Engines with small flywheel |
| D. | Small engines |
| E. | Large capacity engines |
| Answer» D. Small engines | |
| 361. |
In wet dry lubrication of diesel engines |
| A. | Oil is splashed |
| B. | Oil is splashed and pumped to various points |
| C. | Oil is pumped to various points |
| D. | All of the above |
| E. | None of the above |
| Answer» C. Oil is pumped to various points | |
| 362. |
In a velocity compounded impulse turbine, while steam flows through the second row of moving blades |
| A. | The velocity increases |
| B. | The velocity reduces |
| C. | Both velocity as well as pressure increase |
| D. | The velocity remains constant |
| E. | The pressure remains constant |
| Answer» B. The velocity reduces | |
| 363. |
Ignition accelerators are often used for |
| A. | Diesel engine fuels |
| B. | Petrol engine fuels |
| C. | Gas turbine fuels |
| D. | Gas generators |
| E. | All of the above |
| Answer» B. Petrol engine fuels | |
| 364. |
Which one of the following statements is incorrect |
| A. | Combustion is the processes of heat liberation |
| B. | Combustion is a chemical reaction |
| C. | Combustion is rapid oxidation |
| D. | All of the above |
| E. | None of the above |
| Answer» D. All of the above | |
| 365. |
During idling in a compression ignition engine the air fuel ratio may be of the order of |
| A. | 5 |
| B. | 20 |
| C. | 10 |
| D. | 15 |
| E. | 30 |
| Answer» E. 30 | |
| 366. |
Solid injection in diesel engines implies |
| A. | Use of solid fuels |
| B. | Supply of fuel in the form of solid |
| C. | Injecting fuel with lubricating oil |
| D. | Injecting fuel and air simultaneously |
| E. | Injecting fuel without air |
| Answer» E. Injecting fuel without air | |
| 367. |
Which fuel has maximum resistance to detonation |
| A. | Alcohol |
| B. | n-Heptane |
| C. | Toulene |
| D. | Iso-octane |
| E. | Benzene |
| Answer» D. Iso-octane | |
| 368. |
The level of oil in engine cylinder should be checked when the engine is |
| A. | Not running |
| B. | Running |
| C. | During starting |
| D. | During cranking |
| E. | None of the above |
| Answer» A. Not running | |
| 369. |
The molecular weight of a mixture containing 20% oxygen, 20 percent nitrogen and 60 percent carbon dioxise on volume bases will be nearly |
| A. | 38.4 |
| B. | Carbon dioxide |
| C. | 41.4 |
| D. | 29.9 |
| E. | 33.3 |
| Answer» A. 38.4 | |
| 370. |
Dissociation is |
| A. | Process of heat liberation in which no flame exist |
| B. | Same is combustion |
| C. | Combustion without heat |
| D. | Slow combustion |
| E. | Smokeless combustion |
| Answer» B. Same is combustion | |
| 371. |
Thermodynamic processes are those |
| A. | Where a difference is observed in any macroscopic property of the system between different times or state |
| B. | Where a difference is observed in any microscopic property of the system between different times or state |
| C. | Which occurs in the direction of an intensive property or driving force contained within the system |
| D. | Which require an agency outside the system to force the process |
| E. | None of the above |
| Answer» A. Where a difference is observed in any macroscopic property of the system between different times or state | |
| 372. |
A Lungistrom turbine is a |
| A. | Radial flow reaction turbine |
| B. | Axial flow reaction turbine |
| C. | Radial flow impulse turbine |
| D. | Mixed flow impulse turbine |
| E. | None of the above |
| Answer» A. Radial flow reaction turbine | |
| 373. |
Highest useful compression ratio is the compression ratio at which |
| A. | An engine can be safely operated |
| B. | An engine gives maximum thermal efficiency |
| C. | An engine operates smoothly |
| D. | Detonation first becomes audible |
| E. | None of the above |
| Answer» D. Detonation first becomes audible | |
| 374. |
The pour point of diesel fuel oil must be |
| A. | More than the coldest atmospheric temperature at which oil is to be pumped |
| B. | Less than 0?C |
| C. | Less than the coldest atmospheric temperature of which oil is to be pumped |
| D. | More than 100?C |
| E. | More than 0?C |
| Answer» C. Less than the coldest atmospheric temperature of which oil is to be pumped | |
| 375. |
The emission of carbon monoxide in automobile exhaust will be low when the vehicle is |
| A. | Cruising at low speeds |
| B. | Idling |
| C. | Decelerating |
| D. | Cruising at high speeds |
| E. | Accelerating |
| Answer» D. Cruising at high speeds | |
| 376. |
In a four stage compressor system first and third stage pressures are 1 and 9 kg/cm2 respectively. What will be the fourth stage delivery pressure |
| A. | 243 kg/cm2 |
| B. | 81 kg/cm2 |
| C. | 3 kg/cm2 |
| D. | 27 kg/cm2 |
| E. | 9 kg/cm2 |
| Answer» B. 81 kg/cm2 | |
| 377. |
In a lead cell battery the voltage per cell is |
| A. | 6 volts |
| B. | 1 volt |
| C. | 1.5 volt |
| D. | 2 volts |
| E. | 1.1 volt |
| Answer» D. 2 volts | |
| 378. |
Ignition quality of diesel fuel is expressed by |
| A. | Octane number |
| B. | Cetane number |
| C. | Carbon percentage |
| D. | Calorific value |
| E. | None of the above |
| Answer» B. Cetane number | |
| 379. |
The use of Wilson's line for flow calculation is associated with |
| A. | Impulse turbines |
| B. | Reaction turbines |
| C. | Diesel engines |
| D. | Steam-nozzles |
| E. | Gas turbines |
| Answer» D. Steam-nozzles | |
| 380. |
Rateau turbine is a |
| A. | Velocity compounded impulse turbine |
| B. | Pressure compounded reaction turbine |
| C. | Velocity compounded reaction turibine |
| D. | Pressure compounded impulse turbine |
| E. | Pressure-velocity compounded turbine |
| Answer» D. Pressure compounded impulse turbine | |
| 381. |
Centrifugal blowers can supply |
| A. | Large volumes of air at low pressures |
| B. | Large volumes of air at high pressures |
| C. | Small volumes of air at high pressures |
| D. | Small volumes of air at low pressures |
| E. | None of the above |
| Answer» A. Large volumes of air at low pressures | |
| 382. |
To augment the thrust of jet propulsion units part of the fuel is burned in the exhaust. How does this fuel burn |
| A. | Some chemicals rich in oxygen are mixed with fuel |
| B. | Oxygen is also supplied along with fuel |
| C. | 600;1 |
| D. | Fuel is never burned in exhaust pipe |
| E. | Fuel finds oxygen from excess air supplied to engine |
| Answer» E. Fuel finds oxygen from excess air supplied to engine | |
| 383. |
Intake air filters are provided on air compressor for |
| A. | Removing dirt and dust from suction air |
| B. | Reducing temperature of suction air |
| C. | Reducing pressure of suction pressure |
| D. | Removing impurities of air |
| E. | None of the above |
| Answer» A. Removing dirt and dust from suction air | |
| 384. |
Which one of the following factors will not assist in getting high power output from a compression ignition engine |
| A. | High compression ratio |
| B. | Fine atomisation of fuel |
| C. | High charge density |
| D. | Large quantity of excess air |
| E. | None of the above |
| Answer» D. Large quantity of excess air | |
| 385. |
The lowest temperature upto which a mercury thermometer can be used is |
| A. | ? 39?C |
| B. | ? 260?C |
| C. | ? 173?C |
| D. | ? 10?C |
| E. | 0?C |
| Answer» A. ? 39?C | |
| 386. |
In case of a condensing turbine the pressure in the last stage of the turbine is |
| A. | Same as atmospheric pressure |
| B. | Slightly above the atmospheric pressure |
| C. | 5 to 6 kg/cm2 above the atmospheric pressure |
| D. | Less than the atmospheric pressure |
| E. | 10 to 12 kg/cm2 above the atmospheric pressure |
| Answer» D. Less than the atmospheric pressure | |
| 387. |
The blades of a turbine are made of |
| A. | High speed steel |
| B. | Cast iron |
| C. | Alloy steel |
| D. | Nickel alloy |
| E. | Stainless steel |
| Answer» D. Nickel alloy | |
| 388. |
The frictional horse power of a well adjusted petrol engine should be nearly |
| A. | 50% |
| B. | 40% |
| C. | 25% |
| D. | Carbon dioxide |
| E. | 10% |
| Answer» E. 10% | |
| 389. |
LPG stands for |
| A. | Liquefied petroleum gas |
| B. | Low pressure gas |
| C. | Light pressure gas |
| D. | Lubricated petroleum gas |
| E. | None of the above |
| Answer» A. Liquefied petroleum gas | |
| 390. |
The term scavanging is generally associated with |
| A. | High speed engines |
| B. | Air cooled engines |
| C. | Multi-cylinder engines |
| D. | Two stroke engines |
| E. | Vertical engines |
| Answer» D. Two stroke engines | |
| 391. |
Solubility of a gas in a liquid at small concentration is represented in |
| A. | Henry's law |
| B. | Clausius Clapeyron equation |
| C. | Raoult's law |
| D. | Dalton's law |
| E. | None of the above |
| Answer» A. Henry's law | |
| 392. |
The engine provided on scooters is generally |
| A. | Four stroke, air cooled |
| B. | Four cylinder, air cooled |
| C. | Two stroke, double acting |
| D. | Two stroke, air cooled |
| E. | Four stroke, water cooled |
| Answer» D. Two stroke, air cooled | |
| 393. |
The instrument used for the measurement of area of p-v diagram is known as |
| A. | Digitometer |
| B. | Clinometer |
| C. | Planimeter |
| D. | Areameter |
| E. | Graphometer |
| Answer» C. Planimeter | |
| 394. |
If in a compression ignition engine the noise level is to be reduced, the design features which will not be affected are |
| A. | Combustion system |
| B. | Exhaust muffling |
| C. | Intake muffling |
| D. | Fuel injection equipment |
| E. | None of the above |
| Answer» D. Fuel injection equipment | |
| 395. |
For dry saturated steam the value of adiabatic index n is taken as |
| A. | 1.135 |
| B. | 1.41 |
| C. | 1.35 |
| D. | 25 to 30 |
| E. | 1.68 |
| Answer» A. 1.135 | |
| 396. |
In a petrol engine the mixture strength for maximum power is |
| A. | 1 ; 5 |
| B. | Carbon dioxide |
| C. | 1 ; 30 |
| D. | 1 ; 23 |
| E. | 1 ; 13 |
| Answer» E. 1 ; 13 | |
| 397. |
The main purpose of compounding in case of steam turbines is to |
| A. | Reduced speed of rotor |
| B. | Reduced exist losses |
| C. | Improve thermal efficiency |
| D. | All of the above |
| E. | None of the above |
| Answer» D. All of the above | |
| 398. |
Which of the following is not the same as watt? |
| A. | Joule/sec |
| B. | Amperes/volt |
| C. | Ampere x volt |
| D. | (Ampere)2 x ohm |
| E. | None of the above |
| Answer» B. Amperes/volt | |
| 399. |
In an engine radiator, heat is transferred by |
| A. | Conduction |
| B. | Convection |
| C. | Radiation |
| D. | Conduction and convection |
| E. | None of the above |
| Answer» D. Conduction and convection | |
| 400. |
A rich mixture will have an air-fuel ratio |
| A. | Less than chemically correct |
| B. | More than chemically correct |
| C. | Chemically correct |
| D. | Any of the above |
| E. | None of the above |
| Answer» A. Less than chemically correct | |
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