DC Boiler Exam ACTUAL EXAM COMPLETE 240
QUESTIONS AND CORRECT DETAILED ANSWERS
(VERIFIED ANSWERS) |ALREADY GRADED A+||ALREADY
GRADED A+
Area of a rectangle - ✔✔ANSWER✔✔-Length x Width
Area of a Circle - ✔✔ANSWER✔✔-.7854 x Diameter²
Volume of a Box - ✔✔ANSWER✔✔-Length x Width x Height
Volume of a Cylinder - ✔✔ANSWER✔✔-.7854 x Diameter² x
Length
Circumference of a Circle - ✔✔ANSWER✔✔-π x Diameter
Unit of Force - ✔✔ANSWER✔✔-Pound (lb)
Formula for Force - ✔✔ANSWER✔✔-Pressure ÷ Area
Unit of Work - ✔✔ANSWER✔✔-in-lb or ft-lb
Formula for Work - ✔✔ANSWER✔✔-Force x Distance
Unit of Power - ✔✔ANSWER✔✔-ft-lb/min
Formula for Power - ✔✔ANSWER✔✔-= Work ÷ Time
or (Force x Distance) ÷ Time
,Formula for Mechanical Horsepower - ✔✔ANSWER✔✔-=
Power ÷ 33,000 ft-lb/min
Fahrenheit to Celsius - ✔✔ANSWER✔✔-°C = (°F - 32) ÷ 1.8
Celsius to Fahrenheit - ✔✔ANSWER✔✔-°F = (1.8 x °C) - 32
Fahrenheit to Rankine - ✔✔ANSWER✔✔-°R = °F + 460
Celsius to Kelvin - ✔✔ANSWER✔✔-K = °C +273.15
Charles' First Law - ✔✔ANSWER✔✔-Volume1 / Pressure1 =
Volume2 / Pressure2
Charles' Second Law - ✔✔ANSWER✔✔-Pressure1 /
Temperature1 = Pressure2 / Temperature2
Boyle's Law - ✔✔ANSWER✔✔-Pressure1 x Volume1 =
Pressure2 x Volume2
General Gas Law - ✔✔ANSWER✔✔-(Pres1 x Vol1)/ Temp1 =
(Pres2 x Vol2)/Temp2
Formula for Levers - ✔✔ANSWER✔✔-Resistance x DistanceR
= Effort x DistanceE
Formula for Inclined Planes - ✔✔ANSWER✔✔-Force x Length
= Resistance x Height
Formula for Wheel & Axel - ✔✔ANSWER✔✔-Force x
DistanceF = Resistance x DistanceR
Torque - ✔✔ANSWER✔✔-Force x Radius
, Safe Working Pressure of a Riveted Boiler (SWP) -
✔✔ANSWER✔✔-(Area of Staybolt x Stress Constant of
Staybolt) ÷ Area Covered by Staybolt or = (a x C) ÷ A
Area Covered by Staybolt - ✔✔ANSWER✔✔-= Pitch x Pitch
Longitudinal Stress - ✔✔ANSWER✔✔-(P x D x L) / 2t
P = Pressure
D = Diameter
L = Length
t = thickness of steel
Boiler Heating Surface (tubes) = - ✔✔ANSWER✔✔-= C x L x #
C = Circumference of tubes
L = Length of tubes
# = Number of tubes
HS = π x Diameter x Length x Number of Tubes
Watts per Boiler Horsepower - ✔✔ANSWER✔✔-746 Watts
Horsepower formula - ✔✔ANSWER✔✔-= ft-lb/min ÷ 33000 ft-
lb/min
ft-lb formula for a pump - ✔✔ANSWER✔✔-= gpm x 8.33 x
head (ft)
Factor of Evaporation (FE) = - ✔✔ANSWER✔✔-= [Hs - (tfw-
32)] ÷ 970.3
Hs = Enthalpy of steam
tfw = temperature of feed water
Latent Heat of Vaporization for Water - ✔✔ANSWER✔✔-970.3
Btu/lb
Latent Heat of Fusion for Water - ✔✔ANSWER✔✔-144 Btu/lb
QUESTIONS AND CORRECT DETAILED ANSWERS
(VERIFIED ANSWERS) |ALREADY GRADED A+||ALREADY
GRADED A+
Area of a rectangle - ✔✔ANSWER✔✔-Length x Width
Area of a Circle - ✔✔ANSWER✔✔-.7854 x Diameter²
Volume of a Box - ✔✔ANSWER✔✔-Length x Width x Height
Volume of a Cylinder - ✔✔ANSWER✔✔-.7854 x Diameter² x
Length
Circumference of a Circle - ✔✔ANSWER✔✔-π x Diameter
Unit of Force - ✔✔ANSWER✔✔-Pound (lb)
Formula for Force - ✔✔ANSWER✔✔-Pressure ÷ Area
Unit of Work - ✔✔ANSWER✔✔-in-lb or ft-lb
Formula for Work - ✔✔ANSWER✔✔-Force x Distance
Unit of Power - ✔✔ANSWER✔✔-ft-lb/min
Formula for Power - ✔✔ANSWER✔✔-= Work ÷ Time
or (Force x Distance) ÷ Time
,Formula for Mechanical Horsepower - ✔✔ANSWER✔✔-=
Power ÷ 33,000 ft-lb/min
Fahrenheit to Celsius - ✔✔ANSWER✔✔-°C = (°F - 32) ÷ 1.8
Celsius to Fahrenheit - ✔✔ANSWER✔✔-°F = (1.8 x °C) - 32
Fahrenheit to Rankine - ✔✔ANSWER✔✔-°R = °F + 460
Celsius to Kelvin - ✔✔ANSWER✔✔-K = °C +273.15
Charles' First Law - ✔✔ANSWER✔✔-Volume1 / Pressure1 =
Volume2 / Pressure2
Charles' Second Law - ✔✔ANSWER✔✔-Pressure1 /
Temperature1 = Pressure2 / Temperature2
Boyle's Law - ✔✔ANSWER✔✔-Pressure1 x Volume1 =
Pressure2 x Volume2
General Gas Law - ✔✔ANSWER✔✔-(Pres1 x Vol1)/ Temp1 =
(Pres2 x Vol2)/Temp2
Formula for Levers - ✔✔ANSWER✔✔-Resistance x DistanceR
= Effort x DistanceE
Formula for Inclined Planes - ✔✔ANSWER✔✔-Force x Length
= Resistance x Height
Formula for Wheel & Axel - ✔✔ANSWER✔✔-Force x
DistanceF = Resistance x DistanceR
Torque - ✔✔ANSWER✔✔-Force x Radius
, Safe Working Pressure of a Riveted Boiler (SWP) -
✔✔ANSWER✔✔-(Area of Staybolt x Stress Constant of
Staybolt) ÷ Area Covered by Staybolt or = (a x C) ÷ A
Area Covered by Staybolt - ✔✔ANSWER✔✔-= Pitch x Pitch
Longitudinal Stress - ✔✔ANSWER✔✔-(P x D x L) / 2t
P = Pressure
D = Diameter
L = Length
t = thickness of steel
Boiler Heating Surface (tubes) = - ✔✔ANSWER✔✔-= C x L x #
C = Circumference of tubes
L = Length of tubes
# = Number of tubes
HS = π x Diameter x Length x Number of Tubes
Watts per Boiler Horsepower - ✔✔ANSWER✔✔-746 Watts
Horsepower formula - ✔✔ANSWER✔✔-= ft-lb/min ÷ 33000 ft-
lb/min
ft-lb formula for a pump - ✔✔ANSWER✔✔-= gpm x 8.33 x
head (ft)
Factor of Evaporation (FE) = - ✔✔ANSWER✔✔-= [Hs - (tfw-
32)] ÷ 970.3
Hs = Enthalpy of steam
tfw = temperature of feed water
Latent Heat of Vaporization for Water - ✔✔ANSWER✔✔-970.3
Btu/lb
Latent Heat of Fusion for Water - ✔✔ANSWER✔✔-144 Btu/lb
