IFSTA Chapter 4 & 5 Exam | Questions and Verified Answers| 100% Correct
IFSTA Chapter 4 & 5 Exam | Questions and
Verified Answers| 100% Correct
Q: Which heat transfer mechanism is dependent on several factors including the turbulence and
velocity of moving gases? (132) [4.3.11, 4.3.12]
A. Radiation
B. Reflection
C. Convection
D. Conduction
Answer:
C. Convection
Q: By which mechanism of heat transfer does heat travel in a straight line at the speed of light,
allowing heat to travel through vacuums and air spaces? (134) [4.3.11, 4.3.12]
A. Radiation
B. Reflection
C. Convection
D. Conduction
Answer:
A. Radiation
Q: Heat that is radiated to the insulating air layer between PPE and your body: (135) [4.3.11,
4.3.12]
A. can cause heat stress and failure of the PPE.
B. may cause spontaneous ignition of the PPE materials.
C. dissipates at a much quicker rate than convected heat.
D. is less dangerous than heat conducted to the outside of the PPE.
Answer:
A. can cause heat stress and failure of the PPE.
Q: A fuel’s chemical content influences its heat release rate and its: (136) [4.3.11]
A. convective flow
B. heat of combustion
C. physical attributes
D. organic compounds
Answer:
B. heat of combustion
Q: Gaseous fuels can be the most dangerous of all fuel types because they: (137) [4.3.10,
4.3.11]
A. will sink and collect in low areas.
B. can quickly change into a liquid or a solid fuel.
C. are the most commonly encountered form of fuel.
D. are already in the physical state required for ignition.
Answer:
D. are already in the physical state required for ignition.
Q: What will a liquid with a specific gravity of less than one do when combined with water?
(138) [4.3.10]
A. Sink
B. Float
C. Vaporize
D. Easily mix
Answer:
B. Float
Q: The minimum temperature at which a liquid gives off sufficient vapors to ignite, but not
sustain combustion is its: (139) [4.3.10, 4.3.11]
A. Flash point
B. Vapor pressure
C. Specific gravity
D. Degree of solubility
Answer:
A. flash point.
Q: What may occur if water is added to a burning liquid that is less dense than water? (139)
[4.3.10]
A. The fuel’s rate of vaporization will decrease due to the increased water pressure.
B. The water may disperse the burning liquid instead of extinguishing it.
C. The liquid fuel may vaporize much more rapidly as it draws thermal energy from the water.
D. The water will mix with the burning liquid and become less effective at extinguishing the
fire.
Answer:
B. The water may disperse the burning liquid instead of extinguishing it.
Q: When solid fuels are heated, they begin to __ and release fuel gases and vapors. (139)
[4.3.10, 4.3.11]
A. melt
B. pyrolize
C. hypoxilize
D. evaporate
Answer:
B. pryolize
Q: Sawdust ignites more easily than a log because the sawdust has a higher: (140) [4.3.11]
A. pyrolysis point.
B. surface-to-mass ratio.
C. fuel thickness proportion.
D. flammable (explosive) range.
Answer:
B. surface-to-mass ratio
Q: In most compartment fires, the energy release in fire is directly proportional to the: (140)
[4.3.11]
A. thermal conductivity of the fuel.
B. amount of fuel available for combustion.
C. ambient temperature of the environment.
D. amount of oxygen available for combustion.
Answer:
D. amount of oxygen available for combustion.
Q: Materials that burn at normal oxygen levels will burn more intensely in __
atmospheres. (143) [4.3.11]
A. flaming
B. nonflaming
C. oxygen-enriched
D. oxygen-deficient
Answer:
C. oxygen-enriched
Q: Combustion can occur within a range of concentration of fuel vapor and air; this range is
referred to as the: (143) [4.3.11]
A. vapor pressure range.
B. surface to mass range.
C. flammable (explosive) range.
D. oxidation (combustion) range.
Answer:
C. flammable (explosive) range.
Q: How does the self-sustained chemical reaction influence the oxidation reaction in flaming
combustion? (144) [4.3.11]
A. Increases the speed of the oxidation reaction
B. Decreases the types of products of combustion released
C. Decreases the temperature required for the oxidation reaction
D. Increases the ratio of complete to incomplete combustion of fuel
Powered by https://learnexams.com/search/study?query=