The physics behind toilet seat splatter

For a 6-foot tall man whose urethra lies at his mid-point (3 feet off the ground), standing in front of a toilet that is exactly 1.5 feet off the ground with an opening 1 foot wide, there exists a range of 18° to both the right and left of true vertical in which he can safely aim his stream.

And as we all know, 18° is 20% of 90°. So, the hypothetical male has a 20% margin of error to both the left and right of true vertical. This probably sounds like a reasonable margin of error, BUT until now we have completely discounted the organic shape and surface of the urethra and the head of the willy.

And the urethra's terminus at the tip of the wong is of vital importance! At this junction, the skin parts at approximately 45° to the right and left. This angle in combination with the adhesive properties of water (urine is approximately 95% water) results in a substantial urinary course correction as the water/urine pressure begins to drop toward the end of a bout of urination. In other words, as the bladder empties itself, pressure drops, and urine tends to "stick" to the sides of the urethra/johnson more actively (i.e., as the "straightening" effect of water pressure diminishes, the effect of surface adhesion becomes more pronounced, thus encouraging urine to follow the natural curve at the head of the schlong).

So we now have the potential for a 50% (45° being half of 90°) course correction working against a 20% acceptable margin of error. And this has the makings of disaster...or at least splatter.*

But really, we should have the decency to at least wipe off the seat... ;-)

This is not the physics behind toilet seat splatter. This is only the seeming inability of some men to point their cock accurately at anything but the female pudenda. I am a man, and guess what? My, ahem, urethra apparently is fundamentally different from the one described above. It does not spray urine widely to the sides as I relieve myself. It does not have a "urinary course correction" feature (maybe I need a kernel upgrade?). I can hit the toilet.

Krok7, you deserve kudos for this set of calculations, but it may not apply as universally as you think. The only toilet splatter that is excusable by scientific principles is that from the stream actually splashing in the water, and the only way to avoid that is to sit down. OK, so nobody should demand you sit down to pee all the time. Just MINIMIZE the problem by putting up the seat, and exercising a little self control. Practice in the bathtub with a target if you have to.

Indeed, the only way to reduce splatter is to minimize the amount of urine splash coming from your willy. Since it's not practical to ask guys to sit down, let's add some practicality to this idea and introduce a compromise: pee straight down. Anyone who has ever dove off the high board into a swimming pool knows that the way to enter the water smoothly, with a minimum of splash, is to go in straight. The same principle works for your piss. Peeing straight down means that you have to stand so that your johnson is directly over the bowl of the toilet, so that your stream hits the surface of the toilet's "lake" traveling straight down, perhaps a good three inches away from the "shoreline". This will give you some room for error when the stream's pressure drops. (Note: And by all means, please wipe any stray drops of pee off the rim of the toilet--there won't be that many if you master this technique. And, teach your sons to do the same.)

Note that this same technique works with urinals. In some cases this is perhaps even more effective with urinals, depending on the surface area of the bowl's water, and whether there's some sort of deodorizer device sitting in there, because the stream travels less distance and reduces the margin of error. An idea related to this is the following: In some European countries, they paint images of flies in the bottom of some public urinals. The idea here is that it gives guys a "target" to shoot at and it improves their aim. (And, to emphasize a point, you should always aim straight down.)