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Message: <blockquote data-quote="Greenfield" data-source="post: 5852382" data-attributes="member: 6669384">The basic problem with all these calculations is that the description in the book is inconsistent with anything actually possible.The only way to get an actual 1 foot wide stream of water is to have a 1 foot wide opening.  And it's a decanter, not a bucket.Also, the idea that a spray of water will cease moving after exactly 20 feet, no matter which direction it's facing is, well, a fantasy.Now there are a few things that can be agreed upon.1) At Geyser setting it's producing 5 gallons per second.  That's 40 lbs.  Does 1 count as "a few"?  Because that's the only actual number you can possibly count on.  Or can we even agree on that 1?  The Decanter has an option to produce salt water, which will have a different weight.How different?  Depends on the salinity.  Dead Sea water is about as saline as water can get at that temperature, but as temperature changes so does the ability of water to hold salt in solution.Sea water weighs approximately 8.552 lbs per gallon, though even that is variable based on which part of which sea you're taking it from.  (The Mediterranean is a shallow, warm water ocean so evaporation plays a big factor.  It's saltier than water from the mid Atlantic.)So we have a couple of different values for the M part of the kinetic energy formula, but no way to calculate the V part.  The speed that the water leaves at, in terms of actual velocity, is going to depend on the size of the opening, and if we take the description at its word, that somehow the opening size changes to a foot, you'll have so little action/reaction going there that the only reason for the Strength check would be to hold to weight of the now bucket-sized decanter full of water.If it was possible to move 5 gallons per second through a pinhole (it isn't, fluid dynamics make it impossible), you'd need a release velocity in the thousands of miles per hour.  (Water jet cutters push half a gallon a minute through such a hole, and it comes out with enough force to cut steel.)At 80 psi (common pressure for household water systems) you can move 5 gallons per second through a 1/2 inch opening.  At higher pressures you can get up to 21 gallons per second through that same opening.  More than that starts to generate backpressure turbulence, and you actually begin losing flow rate.Did I mention that hydrodynamics is weird?So the answer is, as usual, that applying physics to a magical fantasy game is a bad idea. At a minimum you need more data than the game system is providing, and you probably need to ignore some of the flatly impossible information.  (Such as a foot wide stream going fast enough to carry 20 feet, but that only carries 5 gallons per second.)The in-game answer?  Whatever the DM says.</blockquote>

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