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Energy storage and light arrows

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DC:
I've been reading and I keep seeing things that say that the lighter the arrow is the less energy from the bow is transferred to it. Can someone explain why in simple English?

Pat B:
I guess more energy is stored with heavier mass than with light mass. It takes more energy to push a heavy arrow than a lighter arrow.

sleek:
A bows limbs have a maximum speed they can snap back to. Any weight on the string ( an arrow ) slows them down. The heavier the arrow, the slower the limbs return. If you put a 1 grain hypothetical arrow on the string and shoot it, the bow will accelerate the one grain arrow until the limbs have reached their maximum speed. With an arrow so light, the max speed will be reached before the end of the power stoke of the bow. For this hypothetical arrow, lets say that its full speed after the first 6 inches of release. All the energy after that is not being used and will be re absorbed by the bow and let off as vibration. With enough energy the bows vibrations can cause it to break. 

With a heavier arrow, say 100 grains, it may take half the power stroke to reach max speed. With a 500 grain arrow, idealy with a 50 pound bow ( 10 grains arrow weight per pound of draw weight AT 28 INCHES ( many forget or dont realise that part ) the arrow will reach maximum speed at the last inch of poeer stroke, right when the string snaps tight at brace height.

Because the formula for energy envolves mass and speed, and speed, the heavier arrow has the most energy because it reached maximum speed with the most weight. It took all the bows energy stored up during the draw and turned it to kenetic energy rather than leaving  any of it behind in the bow.

DC:
Thanks Sleek, I think that's what I was looking for. It makes sense.

TSA:
very well explained.
tell me what you think for draw lengths over 28", what should a person be looking at for GPP- or do you still work on 10gpp- divisible by 28' multiplied by your draw length- whether it is over or under 28".
thanks Sleek!

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