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.
| 401. |
Choose the proper disadvantage of solid fuels out of the given option? |
| A. | they produce lot of smoke |
| B. | they have low ignition temperature |
| C. | they are high in production cost |
| D. | they cannot be easily transported |
| Answer» B. they have low ignition temperature | |
| 402. |
Which is the correct advantage of solid fuels out of the given option? |
| A. | they have low ignition temperature |
| B. | they produce small amount of smoke |
| C. | they have higher calorific value |
| D. | they do not form any clinker |
| Answer» B. they produce small amount of smoke | |
| 403. |
Which fuel is produced by powdering low grade coal with high ash content? |
| A. | coke |
| B. | pulverized coal |
| C. | charcoal |
| D. | briquette coal |
| Answer» C. charcoal | |
| 404. |
Which fuel is prepared by heating bituminous coal continuously for 15 to 18 hours in closed chamber? |
| A. | charcoal |
| B. | anthracite |
| C. | coke |
| D. | briquette coal |
| Answer» D. briquette coal | |
| 405. |
Which fuel is prepared by moulding finely ground coal under pressure? |
| A. | coke |
| B. | charcoal |
| C. | briquette coal |
| D. | lignite |
| Answer» D. lignite | |
| 406. |
Rotary pumps are driven by |
| A. | electric motors |
| B. | batteries |
| C. | diesel engines |
| D. | biogas fuel |
| Answer» B. batteries | |
| 407. |
What is the function of the feed water pump of a boiler? |
| A. | pump water at high pressure |
| B. | to pump water at lower pressure |
| C. | to pull back the water from boiler |
| D. | to convert steam into water after the boiler process |
| Answer» B. to pump water at lower pressure | |
| 408. |
What is the function Air heater in the boiler? |
| A. | preheat the air before entering the boiler |
| B. | recover the heat from flue gas |
| C. | heating of economizer tubes |
| D. | reheat the gas coming out of economizer |
| Answer» C. heating of economizer tubes | |
| 409. |
What is the function of superheater in the boiler? |
| A. | increase the temperature of steam |
| B. | reheat the steam |
| C. | superheat the feed water |
| D. | to heat the fuel gas |
| Answer» B. reheat the steam | |
| 410. |
What happens due to high temperature of feeds water in the economizer? |
| A. | fuel consumption increases |
| B. | fuel mechanical efficiency increases |
| C. | fuel consumption decreases |
| D. | fuel mechanical efficiency decreases |
| Answer» D. fuel mechanical efficiency decreases | |
| 411. |
How many types of safety valves are used in boiler in practice? |
| A. | 1 |
| B. | 2 |
| C. | 3 |
| D. | 4 |
| Answer» C. 3 | |
| 412. |
What is the function of safety valves in the boiler? |
| A. | to prevent excessive steam pressure |
| B. | to prevent excessive air pressure |
| C. | to prevent water pressure |
| D. | to prevent from rising temperatures |
| Answer» B. to prevent excessive air pressure | |
| 413. |
other than Steam stop valve in the boiler which is the other similar type of valve used? |
| A. | non-reversible valve |
| B. | transient valve |
| C. | reversible valve |
| D. | junction valve |
| Answer» E. | |
| 414. |
What is the function of fusible plug in the boiler? |
| A. | protect the fire tube |
| B. | to trip on overload |
| C. | to act as a junction switch |
| D. | to maintain pressure |
| Answer» B. to trip on overload | |
| 415. |
What is the function of Blow down valve of a boiler? |
| A. | to remove sludge |
| B. | to build sediments |
| C. | to remove flue gas |
| D. | to remove ash |
| Answer» B. to build sediments | |
| 416. |
What is the function of pressure gauge in the boiler? |
| A. | to indicate steam pressure |
| B. | to indicate water pressure |
| C. | to indicate air pressure |
| D. | to indicate flue gas pressure |
| Answer» B. to indicate water pressure | |
| 417. |
How many level indicators are there in the water level indicator of a boiler? |
| A. | 1 |
| B. | 2 |
| C. | 3 |
| D. | 4 |
| Answer» C. 3 | |
| 418. |
Which are the major types of boilers that are operated in world today? |
| A. | natural circulation boiler |
| B. | forced circulation boiler |
| C. | fire tube boiler |
| D. | once through boiler |
| Answer» E. | |
| 419. |
What is the advantage of having smaller ratio of water to steam space? |
| A. | steam can be generated at a faster even if the boiler is cold |
| B. | increases the rate of evaporation |
| C. | water is made cyclic, i.e., from boiler drum to water tube and back to drum |
| D. | helps in mobilizing the boiler |
| Answer» B. increases the rate of evaporation | |
| 420. |
Which type of boilers use orifice to control the flow circulation? |
| A. | natural circulation boilers |
| B. | forced convection boilers |
| C. | once-through boilers |
| D. | positive forced circulation boilers |
| Answer» C. once-through boilers | |
| 421. |
For a compressible, ideal gas, mass flow rate depends on parameters such as flow area, pressure, temperature, properties of the gas, and |
| A. | avogardo’s number |
| B. | mach number |
| C. | reynold’s number |
| D. | le-grange’ number |
| Answer» C. reynold’s number | |
| 422. |
When the pressure chamber is big, the flow velocities are |
| A. | large |
| B. | negligible |
| C. | constant |
| D. | increasing |
| Answer» C. constant | |
| 423. |
Converging-diverging nozzle is also known as |
| A. | pascal nozzle |
| B. | bernouille’s nozzle |
| C. | toricelli’s nozzle |
| D. | de laval’ nozzle |
| Answer» E. | |
| 424. |
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» B. low, high | |
| 425. |
To refrain from separation in subsonic nozzles, the expansion angle must not be more than |
| A. | 10 degrees |
| B. | 20 degrees |
| C. | 30 degrees |
| D. | 40 degrees |
| Answer» B. 20 degrees | |
| 426. |
Isentropic nozzle flow states about the movement of a gas or fluid through a narrow orifice without an increase or decrease in |
| A. | accelerating |
| B. | decelerating |
| C. | equilibrium |
| D. | exponential increase |
| Answer» C. equilibrium | |
| 427. |
In fluid dynamics, the velocity of the fluid in the stagnation point is |
| A. | zero |
| B. | infinite |
| C. | non-existent |
| D. | negative |
| Answer» B. infinite | |
| 428. |
If the speed of sound is much                  than that of the gas, the gas density will stay constant. |
| A. | smaller |
| B. | larger |
| C. | equal to |
| D. | non-existent |
| Answer» C. equal to | |
| 429. |
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» D. dissipated | |
| 430. |
A train has to negotiate a curve of radius 400m. By how much should the putter rail be raised with respect to inner rail for speed of 48 km/h? The distance between the rails is 1m. |
| A. | 0.20m |
| B. | 0.0454m c) 0.45m |
| C. | d) 0.020m |
| Answer» C. d) 0.020m | |
| 431. |
When moving along a curved path, he |
| A. | leans inwards |
| B. | leans outwards |
| C. | is still |
| D. | leans sideways |
| Answer» B. leans outwards | |
| 432. |
Friction can be increased by |
| A. | using air cushion |
| B. | lubricants |
| C. | using sand |
| D. | using ball bearings |
| Answer» D. using ball bearings | |
| 433. |
How is friction due to air reduced? |
| A. | streamlining |
| B. | lubrication |
| C. | by using ball bearings |
| D. | by polishing |
| Answer» B. lubrication | |
| 434. |
A scooter weighs 120kg f. Brakes are applied so that wheels stop rolling and start skidding. Find the force of friction if the coefficient of friction is 0.4. |
| A. | 60kg f |
| B. | 48kg f |
| C. | 25kg f |
| D. | 32kg f |
| Answer» C. 25kg f | |
| 435. |
A mass of 4kg rests on a horizontal plane. The plane is gradually inclined until at an angle θ= 15° with the horizontal, the mass just begins to slide. What is the coefficient of static friction between the block and the surface? |
| A. | 0.814 |
| B. | 0.27 |
| C. | 1.5 |
| D. | 3.5 |
| Answer» C. 1.5 | |
| 436. |
Which of the following kinetic friction is smaller? |
| A. | limiting friction |
| B. | static friction |
| C. | rolling friction |
| D. | sliding friction |
| Answer» D. sliding friction | |
| 437. |
Which among the following is an assumption of the compressible flow? |
| A. | resistance to flow of object |
| B. | no-slip condition |
| C. | known mass flow rate |
| D. | resistance to flow of heat |
| Answer» C. known mass flow rate | |
| 438. |
Compressible flow mainly deals with |
| A. | solid dynamics |
| B. | liquid dynamics |
| C. | gas dynamics |
| D. | solid and liquid dynamics |
| Answer» D. solid and liquid dynamics | |
| 439. |
Which among the following is the formula for mass flow rate? |
| A. | q = m/p |
| B. | q = mp |
| C. | q = m + p |
| D. | q = m – p |
| Answer» C. q = m + p | |
| 440. |
What is Mach number? |
| A. | speed of object * speed of sound |
| B. | speed of object /speed of sound |
| C. | speed of object + speed of sound |
| D. | speed of object- speed of sound |
| Answer» C. speed of object + speed of sound | |
| 441. |
Pumps increase |
| A. | pressure |
| B. | velocity |
| C. | momentum |
| D. | heat |
| Answer» B. velocity | |
| 442. |
Which among the following is the formula for volumetric flow rate? |
| A. | q = v/a |
| B. | q = av |
| C. | q = a+v |
| D. | q = a-v |
| Answer» C. q = a+v | |
| 443. |
The Prandtl Number approximates |
| A. | momentum diffusivity to thermal diffusivity |
| B. | thermal diffusivity to momentum diffusivity |
| C. | shear stress to thermal diffusivity |
| D. | thermal diffusivity to kinematic viscosity |
| Answer» B. thermal diffusivity to momentum diffusivity | |
| 444. |
With the increase in pressure, the exit velocity |
| A. | decreases |
| B. | increases |
| C. | same |
| D. | independent |
| Answer» B. increases | |
| 445. |
In De Laval Nozzle critical pressure ratio is given by (2/y+1)^(y/y-1). |
| A. | true |
| B. | false |
| Answer» B. false | |
| 446. |
Ratio of critical pressure to inlet pressure in known as |
| A. | none of the mentioned |
| B. | pressure ratio |
| C. | critical pressure ratio |
| D. | isoentropic pressure ratio |
| Answer» D. isoentropic pressure ratio | |
| 447. |
Critical pressure ratio is ratios of pressures at discharge. |
| A. | minimum |
| B. | none of the mentioned |
| C. | optimum |
| D. | maximum |
| Answer» E. | |
| 448. |
Aeroderivative engines release higher emissions. |
| A. | true |
| B. | false |
| Answer» B. false | |
| 449. |
Aeroderivative engines are larger. |
| A. | true |
| B. | false |
| Answer» C. | |
| 450. |
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 | |