NR 307 Midterm - In Class Lecture exam
with complete solutions
What is fire? - ANSWER- combustion or burning, in which substances combine
chemically with oxygen from the air and typically give out bright light, heat, and
smoke.
Photosynthesis formula is? - ANSWER- - CO2 + H2O + solar energy -->
(C6H10O5)n + O
-Photosynthesis requires a large amount of heat which is furnished by the sun.
The Combustion process releases this heat. The tremendous amount of heat that
is produced in the burning process is the major reason that the suppression of
wildfires is such a difficult task and why the use of prescribed fire is a complex
and exacting process requiring knowledgeable and experienced people.
Rapid Oxidation or the Combustion process is? - ANSWER- The combustion
process or rapid oxidation
-4C6H10O5 + 25O2 + ignition
temp --> 24CO2 + 18H2O+5,264,729 kJ
What 3 entities are necessary for combustion? (The Fire Triangle) - ANSWER-
Three things are required in proper combination before ignition and combustion
can take place Heat, Oxygen and Fuel.
1. There must be Fuel to burn.
2. There must be Air to supply oxygen.
3.There must be Heat (ignition temperature) to start and continue the combustion
process.
What are the 4 stages of combustion? - ANSWER- Phase 1 - Preheating
Phase 2- Ignition
Phase 3 - Combustion
Phase 4- Extinction
, Phase 1- Preheating consist of? - ANSWER- • Pilot source raises temps
• Dehydration drives extracts to surface
- Moisture of Extinction: moisture content at which not
enough heat to drive out H2O
• Pyrolysis degrades molecules to volatiles that support
combustion
Phase 2 - Ignition consist of? - ANSWER- • Transition between Pre-ignition and
Combustion
• Sources???
- Lightning, volcanoes, campers, smokers, equipment/railroads, debris burning/
electrical malfunctions, or arson
Phase 3 - Combustion consists of? - ANSWER- - Gaseous (flaming)
• Burning of volatilized gas
- Glowing (smoldering)
Phase 4 - Extinction consists of? - ANSWER- • Transition point for combustion
• When temps < heat of vaporization
What three ways does heat transfer occur? - ANSWER- convection, conduction,
radiation
Conduction is the heat transfer by? - ANSWER- - direct contact
Convection is the heat transfer by? - ANSWER- gas movement
Radiation is the heat transfer by ? - ANSWER- - electromagnetic waves
Fire behavior is affected by? - ANSWER- -weather
-fuels
-terrain
-(Hazards)
Two ways to describe fires? - ANSWER- -intensity
-rate of spread
-variables effects on ecosystems
All green and dead materials located in the upper forest canopy including tree
branches and crowns, snags, moss, and high brush are defined as what type of
fuel? - ANSWER- - aerial fuels
with complete solutions
What is fire? - ANSWER- combustion or burning, in which substances combine
chemically with oxygen from the air and typically give out bright light, heat, and
smoke.
Photosynthesis formula is? - ANSWER- - CO2 + H2O + solar energy -->
(C6H10O5)n + O
-Photosynthesis requires a large amount of heat which is furnished by the sun.
The Combustion process releases this heat. The tremendous amount of heat that
is produced in the burning process is the major reason that the suppression of
wildfires is such a difficult task and why the use of prescribed fire is a complex
and exacting process requiring knowledgeable and experienced people.
Rapid Oxidation or the Combustion process is? - ANSWER- The combustion
process or rapid oxidation
-4C6H10O5 + 25O2 + ignition
temp --> 24CO2 + 18H2O+5,264,729 kJ
What 3 entities are necessary for combustion? (The Fire Triangle) - ANSWER-
Three things are required in proper combination before ignition and combustion
can take place Heat, Oxygen and Fuel.
1. There must be Fuel to burn.
2. There must be Air to supply oxygen.
3.There must be Heat (ignition temperature) to start and continue the combustion
process.
What are the 4 stages of combustion? - ANSWER- Phase 1 - Preheating
Phase 2- Ignition
Phase 3 - Combustion
Phase 4- Extinction
, Phase 1- Preheating consist of? - ANSWER- • Pilot source raises temps
• Dehydration drives extracts to surface
- Moisture of Extinction: moisture content at which not
enough heat to drive out H2O
• Pyrolysis degrades molecules to volatiles that support
combustion
Phase 2 - Ignition consist of? - ANSWER- • Transition between Pre-ignition and
Combustion
• Sources???
- Lightning, volcanoes, campers, smokers, equipment/railroads, debris burning/
electrical malfunctions, or arson
Phase 3 - Combustion consists of? - ANSWER- - Gaseous (flaming)
• Burning of volatilized gas
- Glowing (smoldering)
Phase 4 - Extinction consists of? - ANSWER- • Transition point for combustion
• When temps < heat of vaporization
What three ways does heat transfer occur? - ANSWER- convection, conduction,
radiation
Conduction is the heat transfer by? - ANSWER- - direct contact
Convection is the heat transfer by? - ANSWER- gas movement
Radiation is the heat transfer by ? - ANSWER- - electromagnetic waves
Fire behavior is affected by? - ANSWER- -weather
-fuels
-terrain
-(Hazards)
Two ways to describe fires? - ANSWER- -intensity
-rate of spread
-variables effects on ecosystems
All green and dead materials located in the upper forest canopy including tree
branches and crowns, snags, moss, and high brush are defined as what type of
fuel? - ANSWER- - aerial fuels
