5TH CLASS POWER ENGINEERING EXAM READY - VERIFIED
QUESTIONS AND ANSWERS - COMPREHENSIVE LATEST
VERSION 2026/2027
Q: Define temperature. ANSWER Degree of hotness or coldness.
Q: What is absolute zero? ANSWER -273.15°C or 0 Kelvin.
Q: Define specific heat. ANSWER Heat required to raise 1 kg of a
substance 1°C.
Q: What is latent heat? ANSWER Heat that changes state without
changing temperature.
Q: Define sensible heat. ANSWER Heat that changes temperature without
changing state.
Q: What is conduction? ANSWER Heat transfer through a solid.
Q: What is convection? ANSWER Heat transfer through a fluid
(liquid/gas).
Q: What is radiation? ANSWER Heat transfer through empty space via
electromagnetic waves.
Q: Define pressure. ANSWER Force per unit area.
Q: What is gauge pressure? ANSWER Pressure above atmospheric
pressure.
Q: What is absolute pressure? ANSWER Gauge pressure plus
atmospheric pressure.
Q: What is a vacuum? ANSWER Pressure below atmospheric pressure.
,Q: State Boyle’s Law. ANSWER At constant temp, volume is inversely
proportional to pressure.
Q: State Charles’s Law. ANSWER At constant pressure, volume is directly
proportional to temperature.
Q: What is saturated steam? ANSWER Steam at boiling temperature for
its pressure.
Q: What is superheated steam? ANSWER Steam heated above its
saturation temperature.
Q: Define enthalpy. ANSWER Total heat content of a substance.
Q: What is a BTU? ANSWER Amount of heat to raise 1 lb of water 1°F.
Q: Convert 100°C to Fahrenheit. ANSWER 212°F.
Q: Convert 32°F to Celsius. ANSWER 0°C.
Q: What is the unit of power in the metric system? ANSWER Watt
(Joule/sec).
Q: What does a P-T diagram show? ANSWER Relationship between
Pressure and Temperature.
Q: What is the critical point of water? ANSWER 374°C and 22.1 MPa.
Q: What is a thermocouple? ANSWER Device measuring temperature
using two dissimilar metals.
Q: What is a bimetallic strip? ANSWER Two metals bonded together that
bend when heated.
Q: Define density. ANSWER Mass per unit volume.
Q: Define specific volume. ANSWER Volume per unit mass.
Q: What is specific gravity? ANSWER Ratio of a substance's density to
water's density.
Q: What is a calorie? ANSWER Heat to raise 1 gram of water 1°C.
Q: How is work defined in thermodynamics? ANSWER Force acting
through a distance.
2. Boiler Fundamentals & Types (31-60)
, 31. Q: Define a boiler. ANSWER A closed vessel where water is heated to
generate steam.
32. Q: What is a firetube boiler? ANSWER Hot gases pass through tubes
surrounded by water.
33. Q: What is a watertube boiler? ANSWER Water passes through tubes
surrounded by hot gases.
34. Q: What is a low-pressure steam boiler (ASME)? ANSWER Operates
at 15 psi or less.
35. Q: What is a low-pressure hot water boiler? ANSWER Operates at
250°F or less, 160 psi or less.
36. Q: Name a common firetube boiler. ANSWER Scotch Marine.
37. Q: Name a common watertube boiler. ANSWER D-type, O-type, or A-
type.
38. Q: What is a cast iron sectional boiler? ANSWER Boiler made of
bolted-together cast iron sections.
39. Q: What is a packaged boiler? ANSWER Boiler shipped fully
assembled with burner and controls.
40. Q: What is a wet-back boiler? ANSWER Rear tube sheet is
surrounded by water.
41. Q: What is a dry-back boiler? ANSWER Rear tube sheet has a
refractory lining.
42. Q: What is the steam space? ANSWER Area above the normal water
level in a boiler.
43. Q: What is the mud drum? ANSWER Lower drum in a watertube
boiler collecting sludge.
44. Q: What is furnace volume? ANSWER Space in the boiler where
combustion occurs.
45. Q: What is heating surface? ANSWER Surface area exposed to
combustion gases on one side and water on the other.
46. Q: What is boiler horsepower (BHP)? ANSWER Evaporation of 34.5
lbs of water/hr at 212°F.
QUESTIONS AND ANSWERS - COMPREHENSIVE LATEST
VERSION 2026/2027
Q: Define temperature. ANSWER Degree of hotness or coldness.
Q: What is absolute zero? ANSWER -273.15°C or 0 Kelvin.
Q: Define specific heat. ANSWER Heat required to raise 1 kg of a
substance 1°C.
Q: What is latent heat? ANSWER Heat that changes state without
changing temperature.
Q: Define sensible heat. ANSWER Heat that changes temperature without
changing state.
Q: What is conduction? ANSWER Heat transfer through a solid.
Q: What is convection? ANSWER Heat transfer through a fluid
(liquid/gas).
Q: What is radiation? ANSWER Heat transfer through empty space via
electromagnetic waves.
Q: Define pressure. ANSWER Force per unit area.
Q: What is gauge pressure? ANSWER Pressure above atmospheric
pressure.
Q: What is absolute pressure? ANSWER Gauge pressure plus
atmospheric pressure.
Q: What is a vacuum? ANSWER Pressure below atmospheric pressure.
,Q: State Boyle’s Law. ANSWER At constant temp, volume is inversely
proportional to pressure.
Q: State Charles’s Law. ANSWER At constant pressure, volume is directly
proportional to temperature.
Q: What is saturated steam? ANSWER Steam at boiling temperature for
its pressure.
Q: What is superheated steam? ANSWER Steam heated above its
saturation temperature.
Q: Define enthalpy. ANSWER Total heat content of a substance.
Q: What is a BTU? ANSWER Amount of heat to raise 1 lb of water 1°F.
Q: Convert 100°C to Fahrenheit. ANSWER 212°F.
Q: Convert 32°F to Celsius. ANSWER 0°C.
Q: What is the unit of power in the metric system? ANSWER Watt
(Joule/sec).
Q: What does a P-T diagram show? ANSWER Relationship between
Pressure and Temperature.
Q: What is the critical point of water? ANSWER 374°C and 22.1 MPa.
Q: What is a thermocouple? ANSWER Device measuring temperature
using two dissimilar metals.
Q: What is a bimetallic strip? ANSWER Two metals bonded together that
bend when heated.
Q: Define density. ANSWER Mass per unit volume.
Q: Define specific volume. ANSWER Volume per unit mass.
Q: What is specific gravity? ANSWER Ratio of a substance's density to
water's density.
Q: What is a calorie? ANSWER Heat to raise 1 gram of water 1°C.
Q: How is work defined in thermodynamics? ANSWER Force acting
through a distance.
2. Boiler Fundamentals & Types (31-60)
, 31. Q: Define a boiler. ANSWER A closed vessel where water is heated to
generate steam.
32. Q: What is a firetube boiler? ANSWER Hot gases pass through tubes
surrounded by water.
33. Q: What is a watertube boiler? ANSWER Water passes through tubes
surrounded by hot gases.
34. Q: What is a low-pressure steam boiler (ASME)? ANSWER Operates
at 15 psi or less.
35. Q: What is a low-pressure hot water boiler? ANSWER Operates at
250°F or less, 160 psi or less.
36. Q: Name a common firetube boiler. ANSWER Scotch Marine.
37. Q: Name a common watertube boiler. ANSWER D-type, O-type, or A-
type.
38. Q: What is a cast iron sectional boiler? ANSWER Boiler made of
bolted-together cast iron sections.
39. Q: What is a packaged boiler? ANSWER Boiler shipped fully
assembled with burner and controls.
40. Q: What is a wet-back boiler? ANSWER Rear tube sheet is
surrounded by water.
41. Q: What is a dry-back boiler? ANSWER Rear tube sheet has a
refractory lining.
42. Q: What is the steam space? ANSWER Area above the normal water
level in a boiler.
43. Q: What is the mud drum? ANSWER Lower drum in a watertube
boiler collecting sludge.
44. Q: What is furnace volume? ANSWER Space in the boiler where
combustion occurs.
45. Q: What is heating surface? ANSWER Surface area exposed to
combustion gases on one side and water on the other.
46. Q: What is boiler horsepower (BHP)? ANSWER Evaporation of 34.5
lbs of water/hr at 212°F.
