Post/Author/DateTime	Post
Vokkyt 04-04-07, 01:32 PM	What happens to a character's velocity when they go Ethereal? Does it dissipate, or does the velocity carry over to the Ethereal realm? Or, the little known third option, does the velocity resume after the character returns to the Material Plane? According to the DMG, Characters do not fall or receive fall damage in the Ethereal plane...but then again, basic physics dictates that the energy attained during the fall wouldn't simply disappear. Example for clarity: A 15th level Ninja (CAdv) it atop a cliff keeping watch over a ravine where the rest of the party sleeps. The Ninja spots an enemy moving towards the camp, but due to the size of the cliff, the Ninja won't make it down before the enemy gets there. The Ninja decides to jump off of the cliff into the ravine. About 30 ft. off th ground, it goes ethereal and... A) Continues moving at their current velocity downwards in the ethereal plane B) Instantly stops (nonabrasive stop) in the Ethereal Plane and reemerges 6 seconds later C) Instantly stops (nonabrasive stop) in the Ethereal Plane, but when it reemerges, it resumes its velocity from before. I'm not really sure what to do with this one, since I haven't found any text related to Velocity and Ethereal (since it seems to assume that you will always be stationary and grounded)
ArcTan 04-04-07, 01:47 PM	What happens to a character's velocity when they go Ethereal? Does it dissipate, or does the velocity carry over to the Ethereal realm? Or, the little known third option, does the velocity resume after the character returns to the Material Plane? According to the DMG, Characters do not fall or receive fall damage in the Ethereal plane...but then again, basic physics dictates that the energy attained during the fall wouldn't simply disappear. Example for clarity: A 15th level Ninja (CAdv) it atop a cliff keeping watch over a ravine where the rest of the party sleeps. The Ninja spots an enemy moving towards the camp, but due to the size of the cliff, the Ninja won't make it down before the enemy gets there. The Ninja decides to jump off of the cliff into the ravine. About 30 ft. off th ground, it goes ethereal and... A) Continues moving at their current velocity downwards in the ethereal plane B) Instantly stops (nonabrasive stop) in the Ethereal Plane and reemerges 6 seconds later C) Instantly stops (nonabrasive stop) in the Ethereal Plane, but when it reemerges, it resumes its velocity from before. I'm not really sure what to do with this one, since I haven't found any text related to Velocity and Ethereal (since it seems to assume that you will always be stationary and grounded) A) makes the most sense to me. Going ethereal shouldn't be a free way to dissipate falling energy into nothing, and it both makes more intuitive sense and is cooler if doing so instead causes you to fall through the ground, meaning that if you reappear six seconds later you're going to be hurting from the telefrag damage. Once you're in the Ethereal you can use your ability to move in the Ethereal to slow yourself down and stop and float upwards back through the ground again, but this should realistically take some time.
Despana 04-04-07, 01:50 PM	According to the DMG, Characters do not fall or receive fall damage in the Ethereal plane...but then again, basic physics dictates that the energy attained during the fall wouldn't simply disappear. Just remember one thing: D&D and physics have only a passing knowledge of each other's existence. Too much of either in the other causes huge headaches.
daimyotx 04-04-07, 01:59 PM	Why penalize someone for pursuing a PC class long enough to get to 15th level (or such) and obtain the really nice abilities? I'd go with B. - If you need to explain it in physics, you can say the substance of the Ethereal Plane leaches of the excess kinetic energy from the physical act of falling. Just remember - this is D&D - the rules are in place to make things make some semblance of sense, but not to equate to real world laws of mundane physics on a 1 for 1 basis. Otherwise fireball would be impossible without venturing into quantum physics and thermodynamics. Magic is the "theoretical science" that allows all of this. The Ninja would have a good idea by jumping off the cliff and burning up a use of a class ability to warn his party.
lears_fool 04-04-07, 02:10 PM	From the SRD: Ethereal creatures pass through and operate in water as easily as air. Ethereal creatures do not fall or take falling damage. Not only don't they take falling damage, they also don't fall. It appears they simply don't have those particular laws on the Ethereal plane With that in mind, a) is not an option and c) is exceedingly unlikely. So, that leaves two options, b) or, even more likely, the character actually gets to move as an ethereal creature for the duration of his turn (does the ninja ability allow him to move? or is he fixed in place while ethereal?). if he's not fixed in place he should be allowed to move normally in all three dimensions. And it's hardly game-breaking, he's using his potent 15th level ability as a 'feather fall'
calronmoonflower 04-04-07, 03:23 PM	What happens to a character's velocity when they go Ethereal? Does it dissipate, or does the velocity carry over to the Ethereal realm? Or, the little known third option, does the velocity resume after the character returns to the Material Plane? According to the DMG, Characters do not fall or receive fall damage in the Ethereal plane...but then again, basic physics dictates that the energy attained during the fall wouldn't simply disappear. Example for clarity: A 15th level Ninja (CAdv) it atop a cliff keeping watch over a ravine where the rest of the party sleeps. The Ninja spots an enemy moving towards the camp, but due to the size of the cliff, the Ninja won't make it down before the enemy gets there. The Ninja decides to jump off of the cliff into the ravine. About 30 ft. off th ground, it goes ethereal and... A) Continues moving at their current velocity downwards in the ethereal plane B) Instantly stops (nonabrasive stop) in the Ethereal Plane and reemerges 6 seconds later C) Instantly stops (nonabrasive stop) in the Ethereal Plane, but when it reemerges, it resumes its velocity from before. I'm not really sure what to do with this one, since I haven't found any text related to Velocity and Ethereal (since it seems to assume that you will always be stationary and grounded) Well I'll try to apply my limited (and maybe flawed) understanding of physics to the problem. 1. A ethereal creature has no weight. Is this from a lack of gravity on the ethereal plane? No because you gain a fly speed. Free fall doesn't grant a fly speed. 2. If it is not a matter of gravity, then you lack mass. 3. If you have no mass, you have no momentum. That would cause you to come to a full stop with no G-forces like being thrown forward in a braking car. 4. Energy cannot be created or destroyed. Where did the kinetic energy of falling go? 5. Logic and physics do not need to apply in D&D. You can rule that they resume the momentum that they have before becoming ethereal when they resume being material or that it dissipated into the ether.
tos_shai_hulud 04-04-07, 03:54 PM	According to RAW, the ethereal plane has no gravity: SRD rules for the Ethereal Plane (http://www.d20srd.org/srd/planes.htm#theEtherealPlane). Using that knowledge, we know that acceleration ceases when the ninja reaches the ethereal plane. Since the maximum falling damage is 20d6, we can assume that terminal velocity in the D&D world is based on that figure. 1d6 is the amount of damage from falling 10 feet, so in order to determine terminal velocity, I will assume that the force of impact from 10 feet of falling is what deals the 1d6 falling damage. Solving for the velocity, terminal velocity is 160 feet/second, or close to 1000 feet per round (this assumes earth normal gravity). Now, going from that speed to a stop in six seconds produces a G force of less than one. Coming to a stop from that speed requires a distance of 480 feet. I am not sure that all of my mathematics is correct, but it does come out fairly close. Of course, reaching terminal velocity is tough. It stands to reason that since matter does exist in the ethereal plane, drag also exists. Especially since a person who begins moving does not continue moving. The real issue is whether a person traveling at a certain speed would be capable of slowing down (consider move speed of 500 when at terminal velocity). At that point it is up to you. Would the drag forces, combines with a character's own movement, be enough to generate less than one G of force to halt the character. When they do stop, will they be 450 feet into the ground?
Vokkyt 04-04-07, 04:09 PM	Thank you for the responses. In game we allowed the action to go through because a) There wasn't anything explicitly against it and b) it sounded really cool. After reading your responses, I think I'm going to assume that the process of going to the Ethereal plane removes the said velocity when they travel. I had been thinking about this for some time, and my reasoning is that you are effectively shunting yourself to another plane of existence, which means that as soon as the PC appears in the Ethereal plane, it's laws of physics apply, meaning that the energy is automatically dissipated by the properties of the plane.
Vokkyt 04-04-07, 04:13 PM	4. Energy cannot be created or destroyed. Where did the kinetic energy of falling go? Based off of my above assumption, I'm going to assume that the energy is carried over to the Ethereal plane, and it gets dispersed throughout the plane.
calronmoonflower 04-04-07, 04:32 PM	Based off of my above assumption, I'm going to assume that the energy is carried over to the Ethereal plane, and it gets dispersed throughout the plane. I covered that in 5 under "it dissipated into the ether". Perhaps I was just unclear in what I meant.
Vokkyt 04-04-07, 05:05 PM	My bad. Sorry for the misreading.