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kenmontana
09-14-2009, 12:33 PM
i read a post today about kinetic energy and it reminded me of a thought i had early on when i started bow hunting and never really checked out. Essentially it has to do with the difference between momentum-roughly the tendency for a object to continue to travel at the same speed and in the same direction unless acted on by an out side force, expressed as mass x velocity and energy which is represented by mass x velocity squared.As you can see they are related though energy values velocity over mass as it is squared. thus 2 arrows of different weight with the same energy leaving the same bow will have different momentums with the heavier arrow having the more of the 2.
in my mind it turns out that in hunting this difference matters. while a bullet"kills" as a function of both a lot depends on energy and the ability of the bullet to destroy tissue in and around the bullet path. With an arrow we are relying on momentum alone and the ability of the arrow to keep traveling deep enough to CUT a vital structure that results in bleeding or lung collapse.
if this all holds together then it seems to me we should really report, look at and care about the momentum of a standardized arrow weight (? ex400 grains or some other number agreed on by hunters wiser than me).
what do you think?

scepterman30x
09-14-2009, 12:56 PM
I concur. I have read many post eluding to the ft lbs. of energy calculation and me not saying anything to avoid argument sake. I my memory serves me correctly kinetic energy (how arrows should be measured for energy) is the best way to denote how well an arrow penetrates.