🚀 go-pugleaf

In article <2NOV199209321818@csa2.lbl.gov> sichase@csa2.lbl.gov (SCOTT I CHASE) writes:

>I don't think so.  It's not the kinetic energy which knocks you down - it's
>the linear momentum.

Actually I suspect it's a combination of energy and momentum.  To
knock down a rifleman you need to provide enough momentum to move
his mass.  However you also need to move him off his balance area
fast enough that he cannot compensate for the motion.  Consider the
typical rifleman's stance with feet spread about 2-2.5 feet apart
along a line approximately parallel to the direction of the shot.
His center of gravity will be about a foot ahead of the rear leg.
In order to knock him down you need to move his center of mass about
1 foot to get it behind that support point.  That means you need to
give him enough kinetic energy to move his mass that one foot in
less than his ~0.75 sec reaction time.