1.

Past Board Question

A pump with capacity Q1 and head H1 is
connected with series with another pump with
capacity Q2 and head H2. What is head
developed if Q2 is less than Q1?

A. 2H2 H1
B. H2 + H1
C. H2 / H1
D. H2H1
Answer: B
1. Past Board Question
At ordinary temperature what substance will behave as insert gas and will not react in combustion
process?

A. Nitrogen
B. Sulphur
C. Hydrogen
D. Carbon
Answer: A
2. Past board questions
Which of the following cycle is deal for spark-ignition reciprocating engine?

A. Diesel cycle
B. Dual cycle
C. Rankine cycle
D. Otto cycle
Answer: D
3. Past board questions
What is the relative humidity when the dew point and dry bulb temperature are equal?

A. 110%
B. 0%
C. 100%
D. 50%
Answer: C
4. Past board questions
Reheating process is normally employed is steam plane when:

A. There is excess steam

B. Subcooling is required
C. Turbine undergoes excessive moisture
D. Dehumidifying is required
Answer: C
5. Past board questions
When was the final removal of water vapour in an absorption refrigeration system occur?
 A. Analyser
B. Generator
C. Condenser
D. Rectifier
Answer: D

6. Past board questions

If the average temperature of liquid of power cycle during heat addition process is as high as possible,
the the thermal efficiency of the cycle will:

A. Increase
B. Remain constant
C. Decrease
D. Zero
Answer: A
7. Past board questions
What is the temperature of lubricant at which it will ignite thus limit its application?

A. Cold point
B. Burning point
C. Flash point
D. Use point
Answer: c
8. Past board questions
What is the heat that is removed from the space to be cooled, which is the same as the heat absorbed by
the cooling coils?

A. Heating capacity
B. Enthalphy
C. Work compression
D. Refrigerating effect
Answer: D
9. Past board questions
An air conditioning system in which water is chilled or cooled and which passes the evaporator coils.

A. Chilled water system

B. Direct expansion
C. Absorption
D. Water circulation system
Answer: A
10. Past board questions
A multi-stage refrigeration system which is realizable in using different refrigerants.

A. Direct
B. Cascade
 C. Flooded
D. Vapour
Answer: B
11. Very large pipe diameter means a thicker wall and high cost. It also means

A. Zero pressure drop

B. High pressure drop
C. Constant temperature
D. Low pressure drop
Answer: B
12. Past board questions
Very large pipe diameter means a thicker wall and high cost. It also means

A. Zero pressure drop

B. High pressure drop
C. Constant temperature
D. Low pressure drop
Answer: B
13. Past board questions
Aside from maintaining appropriate temperature for food cold storage, how is desiccation minimized or
decreased?

A. Low oxygen
B. Maintain humidity ratio
C. Low air circulation
D. Increase humidity ratio
Answer: B
14. Past board questions
During combustion process, only air is supplied and not enough to supply two molecule oxygen per one
molecule of carbon, then the product is:

A. Hydration
B. Carbon monoxide
C. Carbonic acid
D. Carbon dioxide
Answer: B
15. Past board questions
As far as combustion chamber design is considered, the maximum power output of a given engine can
be increased by:

A. Increasing combustion time

B. Increasing combustion chamber volume
C. Decreasing combustion chamber volume
D. Providing small values
Answer: C
16. Past board questions
A water conservation device which employs both air and water is condensed a condenser and cooling
tower combined into one is called:

A. Shell and tube condenser

B. Ait-cooled condenser
C. Water-cooled condenser
D. Evaporative condenser
Answer: D
17. Past board questions
In order to perform efficiently, a power cycle must be communicated with the oustside temperature of its
surroundings and into one is called;

A. Kirchoff’s law
B. Second law of thermodynamics
C. Kelvin-Planck law
D. First law of thermodynamics
Answer: B
18. Past board questions
Water is heated in container, it expand and becomes less dense and lighter. It rises up the container
because of it rises up the container because of its reduce density and replaced by cooler air. As this
process continues, the heat is transferred and disturbed all throughout. What is this mode of heat transfer
called?

A. Condenser
B. Radiation
C. Conduction
D. Convection
Answer: D
19. Past board questions
When required, a regulator water valve in refrigerating system should be
A. On the suction line and compressor line
B. In the water inlet
C. Anywhere in the system
D. In the water outlet
Answer: D

20. Past board questions

When there is no work between the thermodynamic system and its surrounding, the quality of the neat
heat transfer is equal to:

A. Total energy of an open system

B. Temperature of an open system
C. Temperature of an closed system
D. Total energy of a closed system
 Answer: D
21. Past board questions
In order to attain equilibrium in the condenser, the cooling tower range must be _________ with respect
to temperature rise in the condenser.

A. Greater
B. Equal
C. Less
D. Zero
Answer: B
22. Past board questions
If ice will form in a solution of water and salt, then it is at a temperature called:

A. Dew point
B. Freezing point depression
C. Boiling point depression
D. Critical point
Answer: B
23. Past board questions
The flow of the convergent section of a nozzle is always subsonic, if the flow is subsonic. If the flow is
subsonic then the mach number is:

A. Greater that unity

B. Less than unity
C. Near than unity
D. Unity
Answer: b
24. One hundred twenty percent theoretical air was supplied for combustion, what is the equivalent excess
equal to:

A. 20%
B. 100%
C. 240%
D. 120%
Answer: D
25. Past board questions
If Pi is the indicated horsepower and Pb is the indicated horsepower of a compressor, then what is
mechanical efficiency, Em equal to:

A. Em= Pb/Pi
B. Em= Pi/Pb
C. Em= Pb-Pi
D. Em= Pi –Pb
Answer: B
26. Past board questions
 What is the least number of compressor a multistage system that will use?

A. Three
B. Two
C. Four
D. One
Answer: B
27. Past board questions
The relation between the Fahrenheit absolute scale and the celcius absolute scale is:

A. R= 1.8 ok
B. R= 32 ok
C. R= 3.2 ok
D. R= 18 ok
Answer: A
28. Past board questions
The sum of the internal energy and the product of pressure and specific volume is known as the:

A. Enthalpy
B. Entropy
C. Total work
D. Total internal energy
Answer: A
29. Past board questions
A refrigeration control that guards the compressor from overload thought about by abruptly increases
loads resulting from defrosting warm products and others is called:

A. Safety valve
B. Suction hold-back valve
C. Solenoid valve
D. Expansion valve
Answer: B
30. Past board questions
What does fossil-fuel fired power plants release, which in turn produces the key ingredient in acid rain?

A. Nitrogen
B. Sulphur emission
C. Carbon monoxide
D. Carbon dioxide
Answer: B
31. Past board questions
The fraction of the radiation energy incident on a surface which is absorbed by the surface is called:

A. Convection
B. Absorptivity
C. Emission
 D. Radiation
Answer: B
32. Past board questions
Which of the following power plants uses energy from uranium to produce electric power?

A. Diesel powerplant
B. Geothermal plant
C. Nuclear plant
D. Hydroelectric plant
Answer: C
33. Past board questions
Ice cubes added to a glass of water and stirred. Moisture start to form on the outer surface of the glass.
At this point, what is the temperature of the outer surface called?

A. Critical temperature
B. Surface temperature
C. Dew point temperature
D. Saturation temperature
Answer: C
34. Past board questions
The force when applied to a mass of one kilogram will give mass an acceleration of one meter per
second for every second called:

A. Watt
B. Joule
C. Newton
D. Pascal
Answer: C
35. Past board questions
The kinetic energy of a moving fluid is used to isentropically compressed the fluid to state of zero
velocity. The temperature of a moving fluid at the state zero velocity is called:

A. Stagnation temperature
B. Partial temperature
C. Critical temperature
D. Absolute temperature
Answer: A
36. Past board questions
The dew point temperature of the products of combustion in the saturation temperature that corresponds
to the partial pressure of the ________ in products.

A. SO2
B. H2O
C. N2
D. CO2
 Answer: B
37. Past board questions
What do we call a device that is used to boiler operation that will stop the burner or at least send a signal
to operator if the water drops to a low level that is no longer safe?

A. Safety valve
B. Dead – weight valve
C. High water cut off
D. Low water cut off
Answer: D
38. Past board questions
Dry analysis is a fractional analysis of the products of combustion which does not include:

A. Water vapour
B. Carbon dioxide
C. Sulphur dioxide
D. Carbon monoxide
Answer: A
39. Past board questions
The size of a reciprocating pump is stamped on the builder’s plate 3’’ x 4’’ x 6’’. The diameter of the
liquid cylinder is:

A. 5’’
B. 6’’
C. 3’’
D. 4’’
Answer: D
40. Past board questions
One foot water is equal to:
A. 0.4138 lb/in2
B. 68.3 lb/ft2
C. 0.8673 lb/in2
D. 62.43 lb/ft2
Answer: D
41. Past board questions
The freezing point of R-22 is:

A. -109 oF
B. -252 oF
C. -256 oF
D. -211 oF
Answer: C
42. Past board questions
Which of the following is a type of evaporator?
 A. Shell-and-tube-condenser
B. Shell-and-tube-water cooler
C. Oil lantern rings
D. Polyphase motors
Answer: A
43. Past board questions
For brayton cycle, the result of regeneration is:

A. Increase in thermal efficiency

B. Decrease in thermal efficiency
C. Moderate thermal efficiency
D. Low thermal efficiency
Answer: A
44. Past board questions
If the pressure exerted on a liquid is higher than the saturation corresponding to its temperature, the
liquid is a:

A. Saturated liquid
B. Subcooled liquid
C. Superheated liquid
D. Highly superheated liquid
Answer: B
45. Past board questions
In a power driven pump, each piston stroke is displaced by 360o divided the ________.

A. Revolution per minute

B. Bore
C. Length of the stroke
D. Number of cylinders
Answer. D
46. Past board questions
If the air is compressed without discarding heat, then what do you call this kind of compression?

A. Isobaric
B. Isochoric
C. Adiabatic
D. Isothermal
Answer: C
47. Past board questions
If a gas posses internal energy, then it is due to its?

A. Velocity
B. Pressure and volume values
C. Height from a certain datum level
D. Molecular motion
 Answer: D
48. Past board questions
The pressure of ammonia was detected in brine solution. How can ammonia be removed?

A. Freeze the brine

B. Heat the brine to a high temperature enough to free the ammonia
C. Throw the brine solution
D. Lower the temperature of the brine
Answer: B
49. Past board questions
What will happen when the pressure at any point inside a centrifugal pump goes below the vapour
pressure corresponding the temperature of the liquid?

A. Turbulent flow
B. Laminar flow
C. Cavitation
D. Priming
Answer: C
50. Past board questions
What does a negatibe Joule-thompson coefficient means during a throttling process?

A. Fluid pressure is constant

B. Fluid temperature drops
C. Fluid temperature rises
D. Fluid pressure zero
Answer: C
51. Past board questions
For steam power plant increasing the operating pressure of the boiler will:

A. Increase thermal efficiency

B. Decrease thermal efficiency
C. Bring thermal efficiency to zero
D. Make thermal efficiency constant
Answer: A
52. Past board questions
The ratio of the average load of that of the rated capacity of a plant is called:

A. Output power
B. Load factor
C. Demand factor
D. Capacity factor
Answer: D
53. Past board questions
What is the method used to evaluate all welds performed on pressure parts of boiler tube materials?
 A. Hydrostatic test
B. Orsat analysis
C. Vacuum test
D. Radiographic test
Answer: D
54. Past board questions
If the pressure is disregarded in the various other components of a steam of a gas power plant, the
pressure rise in the pump or compressor is _____ to the pressure drop in turbine.

A. Inversely proportional
B. Constant
C. Equal
D. Varying
Answer: C
55. Past board questions
What is the effect on saturated temperature if the pressure of the fluid is decreased?

A. There is no effect
B. Saturation temperature decreases
C. Saturation temperature remains constant
D. Saturation temperature increases
Answer: B
56. Past board questions
If V3 is the cylinder volume after the combustion process of a diesel cycle and V2 is its cylinder volume
before combustion, then calculate the cut-off ratio, r.

A. r = V3 – V2
B. r = V2- V3
C. r = V2/V3
D. r= V3/V2
Answer: D
57. Past board questions
Compare the temperature of discharge vapour refrigerant leaving the compressor of a superheated cycle
and saturated cycle, for the same condensing temperature and pressure.

A. There is no difference
B. Higher for the superheated cycle
C. Higher for the saturated cycle
D. Lower for the superheated cycle
Answer: B
58. Past board questions
A valve that releases steam from the boiler by opening at a pre-determined pressure in order to keep the
steam pressure from rising more than the pressure from which the valve is set is called a

A. Ammonia valve
B. Stop valve
 C. Check valve
D. Safety valve
Answer: D
59. Past board questions
What is the relationship of the capacity of a centrifugal pump, Q, to impeller diameter, D, when there are
two impeller diameter in the same pump?

A. Q is directly proportional to the square of the ratio D

B. Q is inversely proportional to the ratio of D
C. Q is directly proportional to the ratio of D
D. Q is inversely proportional to the square of the ratio of D
Answer: C
60. Past board questions
If Wt is the turbine shaft work of a gas turbine unit, Wc is its compressor shaft work and Q is the heat
supplied in dual, then determine its thermal efficiency.

A. Q/(Wt-Wc)
B. Q/(Wt+Wc)
C. (Wt+Wc)/Q
D. (Wt-Wc)/Q
Answer: D
61. Past board questions
The schedule number of a pipe, N, indicates the thickness of the pipe wall. If the allowable stress of the
pipe is S, then what is the internal pressure equal to?

A. N- s
B. N/S
C. NxS
D. S/N
Answer: C

62. Past board questions

What is the pressure present inside the casting of an impulse turbine?

A. Vacuum
B. Atmospheric pressure
C. Above atmospheric
D. Zero
Answer: B
63. Past board questions
In order to remove the fly ashes from the flue gas, which of the following must a power plant be
equipped with?

A. Condenser
B. Demineralizer
 C. Electrostatic precipitator
D. Desulphurization plant
Answer: C
64. Past board questions
If Hs is the total suction hea of a pump, Hp is its suction surface pressure, and Hf its suction friction
head, then calculate the total suction head Ht.

A. Ht = Hs – Hp – Hf
B. Ht = Hs +Hp – Hf
C. Ht= Hs + Hp +Hf
D. Ht = Hs – Hp + Hf
Answer: C
65. Past board questions
The constant spending of certain percentage of circulated water in a cooling tower in order to prevent
accumulation of dissolved

A. Approach
B. Drift
C. Range
D. Bleed-off
Answer: D
66. Past board questions
What process is employed when the turbine steam power plants experience excessive moisture?

A. Reheating
B. Supercooling
C. Subcooling
D. Freezing
Answer: A
67. Past board questions
A company is interested to produce a water turbine wherein only little energy is required or necessary
because the guide vanes are to be controlled. The turbine must be a:

A. Gas turbine
B. Propeller turbine
C. Kaplan turbine
D. Francis turbine
Answer: C
68. Past board questions
If Et is the total net energy generated by a plant in a certain period of time and Er is the rated net energy
capacity of the plant during the same period of time, then what is the plant operating factor?

A. Er – Et
B. Et / Er
C. Et – Er
D. Er / Et
 Answer: B
69. Past board questions
If W is the work output of a heat engine and H is the total heat output of an engine, then determine its
thermal efficiency, e.

A. e = H/W
B. e = W/H
C. e=WxH
D. e = I – (W – H)
Answer: B
70. Past board questions
which of the following is converted to mechanical energy by water

A. Internal energy
B. Kinetic energy
C. Potential energy
D. Hydraulic energy
Answer: C

71. Past board questions

What must be the value of the available net positive suction head (NPSH) of a centrifugal pump
compared to its required NPSH to avoid losing priming?

A. Available NPSH lesser than required NPSH

B. Available NPSH equal than required NPSH
C. Available NPSH greater than required NPSH
D. Available NPSH constant at all times
Answer: C
72. Past board questions
What type of fuel is used with stationary power plants where gas is available by pipeline?

A. Gaseous fuels
B. Solid fuels
C. Coal
D. Liquid fuels
Answer: A
73. Past board questions
Wb is shaft work of an engine and Wi is the indicated work of an engine, if mechanical friction is
present in the engine mechanism, the:

A. Wb is equal to Wi
B. Wb is less than Wi
C. Wb is proportional to Wi
D. Wb is greater than Wi
 Answer: B
74. Past board questions
What is the saturated pressure at the critical temperature, or the lowest pressure in which a substance can
be in the liquid state at its critical pressure?

A. External pressure
B. Critical pressure
C. Condensing pressure
D. Evaporation pressure
Answer: B
75. Past board questions
What is the significance of a high dielectric strength of lubricating oil?

A. Oil is thick
B. Oil is contaminant-free
C. Oil is thin
D. Oil is not clean
Answer: B
76. Past board questions
Theoretically, what is the effect of the compressor clearance horsepower?

A. Varies in direct proportion

B. Increase power
C. Decrease power
D. There is no effect
Answer: D
77. Past board questions
Compare the refrigerating effect per unit mass of refrigerant circulated for a superheated cycle that
produces useful cooling and a saturated cycle, for the same vaporizing and condensing temperature.

A. Lower for a superheated cycle

B. Greater for a saturated cycle
C. The same
D. Greater for a superheated cycle
Answer: D
78. Past board questions
It is important to take some moisture from the air to dehumidify it if the relative humidity reaches high
levels. To do this, it requires cooling the air:

A. At wet-bulb temperature
B. Above its dew point temperature
C. At critical temperature
D. Below its dew point temperature
Answer: D
79. Past board questions
 What does enthalpy measure in substance

A. Its coldness
B. Its heat content
C. Its humidity
D. Its dew point
Answer: B
80. Past board questions
Pneumatic tools are powered by:

A. Natural gas
B. Air
C. Electricity
D. Steam
Answer: B
81. Past board questions
The pump will not cavitate if the available net positive suction head (NPSH) is:

A. Less than the required NPSH

B. Equal or lesser than the required NPSH
C. Equal or greater than the required NPSH
D. Zero compared to the required NPSH of 1
Answer: C
82. Past board questions
A water-tube condenser has a total of 60 tubes. If these are two passes, then compute the number of
tubes per pass.

A. 6C
B. 15
C. 3C
D. 2
Answer: B
83. Past board questions
If Ev is the volumetric efficiency of a reciprocating pump, then determine SLIP which represents all
losses of capacity given in percentage of the displacement.

A. 1 / Ev
B. 1 – 1 / Ev
C. 1 – Ev
D. Ev + 1
Answer: C
84. Past board questions
What is the relationship of the horsepower of a centrifugal pump, Hp, to the impeller speed, S, if the
pump is at two different rotative speeds?

A. Hp is inversely proportional to the cube of the ratio of S

 B. Hp is directly proportional ro the ratio of S
C. Hp is inversely proportional to the ratio of s
D. Hp is directly proportional to the cube of the ratio of S
Answer: D

85. Past board questions

What is likely to occur when sections of the impeller of a centrifugal pump are handling vapour and
other sections are handling liquid?

A. Erosion of the pump

B. High head and low capacity
C. Excessive vibration
D. Complete failure to operate
Answer: D
86. Past board questions
When vapour compression takes place on one side of the piston and one during one revolution of the
cranckshaft, then the compressor is:

A. Double-acting
B. Four-cycle
C. Two-revolution
D. Single-acting
Answer: D
87. Past board questions
In stirling and erickson cycle, the efficiency can be increased by:

A. Compressibility
B. Superheating
C. Regeneration
D. Subcooling
Answer: c
88. Past board questions
Which of the following is used to control refrigeration compressor capacity?

A. Dehumidifier
B. Check valve
C. Solenoid valve
D. Unloader
Answer: D
89. Past board questions
During cooling and dehumidifying process, sensible and latent heats are removed in the cooling coil, if
Hs is the sensible heat andHt is the total heat transferred, then determine the coil sensible factor.

A. Ht – Hs
 B. Hs – HT
C. Ht / Hs
D. Hs / Ht
Answer: D
90. Past board questions
Based on the PSME code, what should be provided in each stream outlets if two or more boilers will be
connected in parallel?

A. Relief and check valves

B. Non-return and shut-off valves
C. Expansion and shut-off valves
D. Expansion and check valves
Answer: B
91. Past board questions
The diesel cycle is the ideal cycle for a:

A. Absorption
B. Steam-jet
C. Compression-ignition engine
D. Gas turbine
Answer: C
92. Past board questions
If a carnot cycle is at the same maximum and minimum temperatures as a rankine cycle, then how
would you compare the efficiency of a rankine cycle to that of the carnot cycle?

A. Efficiency is the same

B. Higher efficiency
C. Efficiency is higher by 30%
D. Lower efficiency
Answer: D
93. Past board questions
Compute the wall gain load of a load storage room when A is the outside surface area of the wall, D is
the temperature differential across the wall, and U is the overall coefficient of heat transmission.

A. AU/ D
B. D / AU
C. A / DU
D. AUD
Answer: D
94. Past board questions
If m is the mass of dry air and H is the specific enthalpy of the water vapour in air and r is the humidity
ratio, them determine the latent heat of any dry air.

A. m / (r – H)
B. r / (H – m)
C. (m – r) / H
 D. m (r x H)
Answer: D
95. Past board questions
When an electric motor nameplate indicates a ‘’100-kw electric motor" then what does a 100-kw rating
refers to?

A. Thermal energy input

B. Thermal energy output
C. Electrical power output
D. Mechanical power output
Answer: D
96. Past board questions
For a hydraulic power to be transmitted at its maximum what should be the value of loss of head due to
friction if H is the total available head?

A. 11H
B. 1/3H
C. 1/4H
D. 5H
Answer: C
97. Past board questions
The ratio of the average load during a certain time to peak the load occurring during the same period of
time is called:

A. Demand factor
B. Capacity factor
C. Load factor
D. Output factor
Answer: C
98. Past board questions
Based on the PSME Code, what should be the effective temperature of the air to be maintained for
comfort cooling at an air movement from 0.0761 to 0.127 meter per second?

A. 25 – 29 degree C
B. 35 – 39 degree C
C. 20 – 24 degree C
D. 30 – 34 degree C
Answer: C
99. Past board questions
If is R the delivery rate of a pump, H is the total pumping head and e is the efficiency of the pump, them
compute the power required to drive the pump.

A. R/Hxe
B. 1 – (R + H) / e
C. (R x H) / e
D. (H – R) / e
 Answer: C
100. Past board questions
There are three basic boiler types, namely:

A. Water-tub, horizontal tube and cast-iron boilers

B. Cast-iron, fire-tube and water tube boilers
C. Fire-tube, cast-steel and water tube boilers
D. HRT, fire-tube and scotch marine boiler
Answer: B
101. Past board questions
The amount of heat necessary to bring up the temperature of a unit mass of a substance through a unit
degree is called:

A. Specific volume
B. Thermal heat
C. Total heat
D. Specific heat
Answer: D
102. Past board questions
What is the specific gravity of an oil which has a baume reading of g of 28 degrees F

A. 0.215
B. 0.562
C. 0.886
D. 0.774
Answer: C
103. Past board questions
If c is the capacity of the compressor in a refrigeration system and F is the heat rejection factor, the
calculate the condenser load, L

A. L–F–C
B. L–F/C
C. L–CxF
D. L–C/F
Answer: C
104. Past board questions
Based on the PSME Code, what should be the humidity of air to be used for comfort cooling?

A. 75% - 80% relative humidity

B. 50% - 60% relative humidity
C. 60% - 70% relative humidity
D. 70% - 75% relative humidity
Answer: B
105. Past board questions
What is the cause of pressure drop in the boiler, condenser and the piping between different component?
Because of this drop, steam leaving the boiler is at a lower pressure.

A. Positive slip
B. Fluid friction
C. Negative slip
D. Low thermal efficiency

Answer: B