Quiz  /  Thermal Engineering Gate & PSU MCQ Questions With Answers

  • 1. 
    A cold storage is to be maintained at – 5°C while the surroundings are at 35°C. The heat leakage from the surroundings into the cold storage is estimated to be 29 kW. The actual C.O.P. of the refrigeration plant used is one third that of an ideal plant working between the same temperatures. Find the power required to drive the plant

  • 11.58 kJ/s
  • 12.98 kJ/s
  • 12.90 kJ/s
  • 10.98 kJ/s

  • 2. 
    At the given inlet condition, a nozzle is said to be choked when mass flow rate is

  • maximum
  • is discharging into atmosphere
  • zero
  • it is not possible to increase the flow by increasing inlet pressure

  • 3. 
    Odometer is an instrument used for measurement of

  • power
  • Fuel consumption
  • Engine speed
  • distance

  • 4. 
    Power is to be generated from a cement kiln exhaust gas. The applicable type of cogeneration is called

  • topping cycle
  • Carnot cycle
  • bottoming cycle
  • Brayton cycle

  • 5. 
    Under thermal equilibrium, flow of steam is

  • Isentropic
  • Adiabatic
  • Hyperbolic
  • Polytropic

  • 6. 
    De-Laval turbines are mostly used

  • Where low speeds are required
  • For small power purposes and low speeds
  • For large power purposes
  • For small power purposes and high speeds

  • 7. 
    Air having a flow rate of 3.6 kg/s at 7 bar and 170 deg.Celcius expands through a convergent-divergent nozzle into a space at 1.03 bar. Calculate the throat area (sq.mm) of the nozzle. Assume isentropic flow and neglect inlet velocity

  • 1463
  • 3645
  • 2680
  • 2185

  • 8. 
    If air at dry-bulb temperature of 35° C and dew point temperature of 20° C passes through a cooling coil which is maintained at 25° C, then the process would be

  • Sensible cooling
  • Cooling and dehumidification
  • Cooling and humidification
  • Cooling at constant wet bulb temperature

  • 9. 
    What's full form of CI

  • Compression inefficiency
  • Computerised injection
  • Compressed injection
  • Compression ignition

  • 10. 
    Combined cycle is a combination of

  • conventional boiler first followed by cogeneration system
  • Rankine cycle first followed by a Brayton cycle
  • Brayton cycle first followed by a standard Rankine cycle
  • extraction in the first portion and then a condensing cycle

  • 11. 
    Below is the main component of refrigeration system EXCEPT:

  • Compressor
  • Evaporator
  • Condenser
  • Pump

  • 12. 
    When fuel oil with 84.9 % carbon, 11.4 % hydrogen, 3.2 % Sulphur, 0.4 % oxygen and 0.1 % ash by weight is burnt with 20 % excess air, assume complete combustion calculate Total air supplied

  • 6.42 kg/kg of fuel
  • 9.24 kg/kg of fuel
  • 16.72 kg/kg of fuel
  • 19.52 kg/kg of fuel

  • 13. 
    A crankshaft's job in an engine is to:

  • deliver fuel to the cylinders
  • change linear motion into rotational motion
  • keep cylinder heads in place
  • To deliver the power to piston

  • 14. 
    The flow through a nozzle is regarded as

  • constant volume flow
  • constant pressure flow
  • isothermal flow
  • isentropic flow

  • 15. 
    Define refrigeration

  • It is the process of continuous cooling or extraction of heat to below that of the atmosphere from a substance with a help of the external work.
  • It is based on the second law of thermodynamics that the heat can made to flow from cold body to a hot body with the help of external source.
  • used to remove heat from the refrigerated space and reject it to atmosphere.
  • All of above

  • 16. 
    In an impulse reaction turbine, the pressure drops gradually and continuously over

  • Fixed blades
  • Moving blades
  • Both fixed and moving blades
  • None of these

  • 17. 
    In what part of a refrigeration system does the refrigerant change from a hot high pressure vapor to a hot high pressure liquid?

  • Evaporator
  • Condenser
  • Liquid line
  • Suction line

  • 18. 
    The performance of a boiler is NOT measured by the

  • amount of water evaporated per hour
  • steam produced in kg/h
  • steam produced in kg/kg of fuel burnt
  • complete combustion of one kg of fuel per hour

  • 19. 
    The motion of the cam is transferred to the valves through

  • Pistons
  • Rocker Arm
  • Cam shaft Pulley
  • Valve stems

  • 20. 
    In a vapor compression refrigeration plant, the refrigerant leaves the evaporator at 195 KJ/kg and the condenser at 65 KJ/kg. For every kg of refrigerant, the plant can supply per second, a cooling load of

  • 70 KW
  • 130 KW
  • 160 KW
  • 100 KW

  • 21. 
    The velocity of fluid at stagnation point is

  • Zero
  • Infinite
  • Very high positive number
  • Very high Negative

  • 22. 
    Mixture requirements during starting of SI engine is

  • Rich
  • Lean
  • Stoichiometry
  • Best power

  • 23. 
    The velocity of steam leaving the nozzle (V) is given by (where K = Nozzle coefficient or nozzle efficiency, and hd = Enthalpy or heat drop during expansion of steam in a nozzle)

  • V = 44.72 hdkh_d\sqrt{k}hd​k​
  • V = 44.72 khdk\sqrt{h_d}khd​​
  • V = 44.72 khd\sqrt{kh_d}khd​​
  • V = 44.72 khdkh_dkhd​

  • 24. 
    What is done to increase the rate of heat transfer in the Velox boiler?

  • The boiler is heated up to very high range of temperature
  • Combustion gases are circulated through tubes with supersonic speed
  • High grade fuel is made use for the combustion
  • The size of the boiler is changed as it is flexible

  • 25. 
    The pressure at which the steam leaves the nozzle is known as back pressure.

  • Correct
  • Incorrect
Report Question
warning
access_time
  Time