As archers, why do we need to be concerned with such terms as “mechanical advantage”, “momentum”, and “EFOC”?
Adequate penetration appeared to require a total arrow mass of at least 650 grains if any bones at all were encountered. - Dr Ed Ashby
The answer is you don’t, that is, unless you intend to hunt with your bow.
If hunters use a bow in their pursuit of game, they owe it to themselves, and the animals that they hunt, to make every effort to insure good, clean, ethical kills. To accomplish this, it is imperative that one has an in-depth knowledge of their equipment, including knowledge of all the external forces that affect the dynamics of their broadhead and arrow on the way to and during the penetration of their target. A lot of archers will go through their whole hunting career not knowing what these terms mean and how these physical forces effect their arrow penetration and flight.
Congratulations! If you have read this far you are definitely a cut above the norm. The success of a hunt always involves paying attention to detail. We'll assume you have already looked at at least some of the Ashby studies and understand the values he places on these topics. If you have not reviewed Dr. Ashby's studies on these topics, now is a good time. You'll soon see why we got involved in broadhead design and created the TUFFHEAD™.