A firefighter can use an infrared camera/viewer for several things, primarily for finding people trapped in a dark or smoke-filled room (where ordinary visibility is zero), and for finding hot spots behind structural members, where fire may be hidden.
"Courageous firefighter" isn't a word.
A firefighter extinguishes fire to keep people safe.
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a basic firefighter does not use any math but if you are an EO (Engine operator) yes you with use math because you have to do pump operations and hydraulics.
Fire Sciences
a firefighter
Infrared radiation is an electromagnetic wave.
Yes, it can take pix in infrared.
Astronomers use infrared light to map the dust in between stars.
The plural of fireman is firemen. If you want to use inclusive language, then you can say firefighter and firefighters.
Heat is primarily transferred through convection, where hot air rises from the fire and carries heat to the firefighter. Radiation is also a method where the fire emits infrared radiation that can directly heat the firefighter's body.
Yes, you can use an infrared thermometer on a dog to take its temperature.