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Factor 2 23-Apr-2010 At 6:15:49 PM Hendo

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On 23/04/2010 One day Hero wrote:
>Wrong..........fall factors have everything to do with energy dissipation.
>You take potential energy, turn it into kinetic energy, then absorb and
>dissipate all the energy by stretching a rope! No calculation shortcuts
>can change the physics, they can however make it easy for layfolk to work
>stuff out in simple situations. This is not a simple situation, fall factor
>thinking can't solve this problem, go back to energy to work out whats
>happening then reconvert to fall factor so the masses can (semi) understand!

I think the usual definition of fall factor is the length of the fall divided by the amount of rope in the system when it becomes taught (potential uncertainty here). This definition does not explicitly incorporate energy. It is mostly about geometry of the setup (though can be influenced by other things eg belayer taking/giving slack...potentially leading to fall factors greater than 2!). If you change the definition to explicitly incorporate energy then you are talking about something else.

As I understand it fall factor is a measure of the severity of the fall on the rope and less directly on other components of the system. It is only one measure and does not give a complete understanding of the system. As you say energy considerations are important but very difficult to assess. Fall factor is easy to assess especially while climbing and I guess a rule of thumb of sorts.