Getting shot by a handgun

Well, a watt per square meter is a measure of irradiance, so I guess if you integrate that with respect to time you'd get joules per square meter. But I don't know if that gives you anything interesting.

It's reasonable to assume "hackers" reading "Hacker News" are expert enough in hacking to decipher computer talk, but unreasonable to assume they're expert enough in guns to decipher gun talk.

About fifteen years ago I read a book summarizing research into the effects of different types and calibers of handguns and handgun ammunition. (Long story short: Clinton was trying to ban semiautomatic handguns or something, so my dad developed a sudden interest in buying a gun, and he borrowed some books from a friend who was quite an enthusiast.) The study was a survey of thousands of police reports on shootings, and it was done by a law enforcement guy to help law enforcement departments make an intelligent decision about what kinds of guns and ammo to standardize on.

He provided a lot of statistics and made some recommendations, but the overriding theme and message of the book was that the result of shooting someone, or being shot, is unpredictable no matter what kind of weapon is involved. Some examples:

A fatal bullet through the heart can leave a guy up and shooting for over ten seconds -- obviously an eternity for a law enforcement officer in a point-blank shootout.

A guy can get shot and not know it. Police officers are trained to check themselves carefully when any shots are fired, because it has happened that officers thought they were unharmed, went home, laid down to rest, and bled to death.

A guy can be in a shootout and THINK he got shot, and it turns out there's not a mark on him. They get knocked over, feel intense pain, cry out, etc. There were enough of these cases that the researchers were able to find some involving officers who were previously decorated for valor and had in fact been shot before.

A guy can get shot multiple times with a powerful weapon and get lucky, or he can get shot with a tiny weapon and get unlucky. I still remember the story used to illustrate this: a fight between roommates got ugly, and one guy shot the other six times in the chest with a .45. The second guy went to his attic, found his great-grandfather's Civil War-era relic small caliber revolver (something like a .22), went back downstairs, and shot his roommate through the heart, killing him. Forty-eight hours later, his desire for medical care overcame his aversion to getting caught, and he walked into an emergency room. He recovered completely.

The book had a lot of complicated reasoning about the trade-offs involved in choosing handguns and ammunition and made some strong recommendations, but I don't remember any of the specifics. I just remember the author stressing over and over again not to expect any particular result when you shoot somebody.

It depends entirely on where they're hit, and how much adrenaline and man-made drugs are in their blood stream. But as a common saying goes, "it's a gun, not a death ray." It's surprising - shocking even - how much damage some people can take and still keep going.

The use I had in mind was for the energy cost of producing a material of uniform or irrelevant thickness, such as aluminum foil or photovoltaic cells.