Physics behind making fire: The ancient way

[gaki]

Main Question or Discussion Point

Hello. I'm new here and I've started a college level physics course at my college without having any sort of physics background. Nevertheless, I find it quite challenging and fun. I like to understand things from class by applying it to real life. I like to go camping and sometimes I make my camp fires the old old school way, by using a stick and a bow.

http://www.youtube.com/watch?v=NWszLA49swY&feature=related

Something like that ^

Now I'm trying to understand it better. The person creates friction (kinetic energy, right?) by rubbing the stick against wood. The kinetic energy transfers to heat energy after a while, and when the temperature is high enough, it begins to burn the wood.

This is my basic understanding of it. Would anyone care to explain it in a more "physics" "mathematical" way?

Thanks

 

[Bob S]

Kinetic energy per unit time (= power or downward force x RPM) in a limited volume (contact area). Use dry wood to reduce both heat capacity and the thermal conduction away from friction site. Cover friction site with dry tinder. When it is raining, use dry twigs from dead branches near trunk on live (e.g., pine or fir) trees. They are most likely to stay dry.
Bob S