posted
I am currently working with the physics department in our high school and am attempting to create a lab that will calculate the efficincy of levers. Naturally, I am thinking of bow limbs as the levers and the arrow the load.
I am having trouble finding a simple way to calculate stored energy so we can find Dynamic efficiency.
Any ideas out there?
Bob.
-------------------- 66" Osage Royale 57lbs@30 66" Sunset Hill 57lbs@29 68" Two Tracks Echo 46lbs@29 68" Deathwish 51lbs@29 68" Shrew Hill 52lbs@29 Posts: 1247 | From: Dodgeville, WI | Registered: Nov 2007
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posted
If you are thinking specifically of a bow you can use the draw weight as elastic PE. Some conversion would be needed to get it into newtons from pounds, but a quick google search should rectify that.
-------------------- I Corinthians 9 24-25 ...run in such a way so as to obtain the prize! Posts: 1196 | From: Stewartstown, Pa | Registered: Nov 2007
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Measure accurately the draw weight at each inch from brace to 28 inches. Plot them on a graph and solve for the area under the graph. There are some accurizing steps to smooth the graph lines but I think you get the idea.
posted
If you go to the A&H archery site to knowledge base they have a very good explanation of how to determine and I bet if you get in touch with them you might get some help with your project.
Posts: 940 | From: Kingsport,Tn | Registered: Aug 2009
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posted
There is a book out there called "Archery the Technical Side." It is a collection of articles all about the physics of archery. C N Hickman, Paul Klopsteg and Forest Nagler are three of the authors. These writers did this back in (I think) the 1930s but the science hasn't changed.
If you can find that book, it will answer many questions and show the math involved.
-------------------- 9 H Hill bows 3 David Miller bows 2 Black Widow bows USA Archery, Level 4 NTS Coach Posts: 1376 | From: Grand Rapids, Minnesota | Registered: Feb 2009
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