American Journal of Physics
Analysis of a forward karate punch is made as an example of collision mechanics. The energy lost to deformation of an opponent is evaluated, and the deformation is shown to be maximized if contact is made when the fist has the greatest speed. In karate fighting the maximum deformation is obtained by focusing a punch to terminate several centimeters inside an opponent’s body. The average impact force is calculated and compared with that neeeded to break a human bone by stressing it beyond its ultimate bending stress value. Similar breaking forces needed for bricks and wooden boards are also computed. A brief description of breaking demonstrations for the physics classroom is made.
Walker, Jearl D., "Karate Strikes" (1975). Physics Faculty Publications. 98.
Walker, Jearl D. "Karate Strikes." American Journal of Physics 43 (1975): 845-849.
Copyright 1975 American Association of Physics Teachers. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Association of Physics Teachers. The following article appeared in American Journal of Physics 43 (1975): 845-849 and may be found at http://ajp.aapt.org/resource/1/ajpias/v43/i10/p845_s1?isAuthorized=no.