⚙️Mechanical Engineering MCQs
Mechanical Engineering MCQs
488 MCQs351
In locomotive boiler, maximum steam pressure is limited to_______________?
A1 kg/cm2
B5 kg/cm2
C10 kg/cm2
D18 kg/cm2 E. 31 kg/cm2
352
In natural circulation type boiler _______________?
Aheating takes place at bottom and the water supplied at bottom gets converted into the mixture of steam bubbles and hot water which rise to drum
Bwater is supplied in durm and through down-comers located in atmospheric conditon it passes to the water wall and rises to drum in the form of mixture of water and steam
Cfeed pump is employed to supplement natural circulation in water wall type furnace
Dwater is converted into steam in one . pass without any recirculation E. water is fed at atmospheric pressure
353
Duplex feed pumps are used in small steam boilers. These operate on the principle of_________________?
Acentrifugal pump
Baxial flow pump
Cgear pump
Dejector pump E. reciprocating pump
354
While steam expands in turbines, theoretically the entropy________________?
Aremains constant
Bincreases
Cdecreases
Dbehaves unpredictably E. none of the above
355
Adiabatic process is________________?
Aessentially an isentropic process
Bnon-heat transfer process
Creversible process
Dconstant temperature process E. constant enthalpy process
356
Pick up the wrong statement about critical condition of steam___________________?
Alatent heat is zero
Bliquid directly becomes steam
Cspecific volume of steam and liquid is same
Dthis is the maximum pressure limit E. all properties of liquid and steam are same
357
Mechanical equivalent of heat for 1 kcal or Joule’s equivalent is equal to_________________?
A421 kgm
B421 kgm
C539 kgm
D102 kgm E. 75 kgm
358
The evaporation of 15.653 kg of water per hour from and at 100°C is called_________________?
Aevaporative capacity
Bfactor of evaporation
Cequivalent evaporation
Done boiler h.p. E. boiler efficiency
359
During polytropic process_________________?
Aheat transfer takes place across cylinder walls
Bwork is done
Csteam may be wet, dry or superheated after expansion
Dall of the above E. none of the above
360
Cochran boiler is a__________________?
Ahorizontal fire-tube boiler
Bhorizontal water-tube boiler
Cveritcal water-tube boiler
Dvertical fire tube boiler E. forced circulating boiler