handleyj Posted April 16, 2009 Report Share Posted April 16, 2009 So I have a teleporter, and he wants to teleport a parked car 20" above an enemy. When does the car land? This phase? Next segment? Next phase? Quote Link to comment Share on other sites More sharing options...
Greywind Posted April 16, 2009 Report Share Posted April 16, 2009 Re: How Long Does It Take To Fall? 5 segments, assuming no prior downward velocity. Quote Link to comment Share on other sites More sharing options...
PhilFleischmann Posted April 17, 2009 Report Share Posted April 17, 2009 Re: How Long Does It Take To Fall? 40 meters, by my math, I get 3 segments. About 5 m for the first segment, another 15 m for the second, and 25 for the third - that's 45 meters, so it lands toward the end of the third segment. Quote Link to comment Share on other sites More sharing options...
BNakagawa Posted April 17, 2009 Report Share Posted April 17, 2009 Re: How Long Does It Take To Fall? about 2.5887 seconds, assuming no wind resistance. Calculating wind resistance is tricky. (assuming no velocity imparted or preserved by teleportation) Quote Link to comment Share on other sites More sharing options...
Manic Typist Posted April 17, 2009 Report Share Posted April 17, 2009 Re: How Long Does It Take To Fall? All of this is also assuming normal Earth gravity. Quote Link to comment Share on other sites More sharing options...
Edsel Posted April 17, 2009 Report Share Posted April 17, 2009 Re: How Long Does It Take To Fall? I always thought falling velocity in earth gravity, in the Hero System, assumed an increase of 5" per segement until the falling body achieved terminal velocity of 30" per segement. So at 20" altitude the car would fall 5" on segment 1, 10" on segment two and then the last 5" on segement 3 at which time it would have a velocity of 15". Quote Link to comment Share on other sites More sharing options...
Crypt Posted April 17, 2009 Report Share Posted April 17, 2009 Re: How Long Does It Take To Fall? Speed at the impact = √(2gh) where h=height and g=9.8m/s^2 on Earth's surface. = √(2*9.8*40) = 28 m/s A simplification would be to see that as a continual speed so it would take around 40/28= 1.42 secs round up = 2 sec (2 segments.) See Newton's laws for an accurate result with no initial speed (but that's not very useful in a rpg, imho) Quote Link to comment Share on other sites More sharing options...
Sean Waters Posted April 17, 2009 Report Share Posted April 17, 2009 Re: How Long Does It Take To Fall? I always thought falling velocity in earth gravity' date=' in the Hero System, assumed an increase of 5" per segement until the falling body achieved terminal velocity of 30" per segement. So at 20" altitude the car would fall 5" on segment 1, 10" on segment two and then the last 5" on segement 3 at which time it would have a velocity of 15".[/quote'] It does 1 segment = 1 second and so an increase of 5" (10 metres) per second (or per segment) in velocity is as near as makes no difference to an increase of 9.8 m per second. So, 1 segment = 10 metres per second = 10 metres fallen by end of segment 2 segments =20 metres pser second = 30 metres fallen by end of segment 3 segments = 30 metres per second = 60 metres fallen by end of segment 20" is 40 metres so it hits somtime in the third segment doing between 30 and 60 metres per second (15" to 30") It is all in the falling table. I don't necessarily agree with the damage progression for falling, but the distance and velocity calculation is simple and elegant. NB what you can do for more velocity is hold an action, teleport the thing up 20", do so again just as it is about to hit (velocity is preserved for a normal teleport) so it comes out already doing 15" per segment and hits during that segment as if it had fallen 40". You can repeat as often as you can - eventually it will hit before you next get a phase, unless you are SPD 12. NB2 the rule about halving movement straight up doesn't apply to teleport - I only noticed that recently. Quote Link to comment Share on other sites More sharing options...
prestidigitator Posted April 17, 2009 Report Share Posted April 17, 2009 Re: How Long Does It Take To Fall? We also assume characters are 2m tall by default. Do we count the impact when the car hits the ground, or when the car hits "head height." Quote Link to comment Share on other sites More sharing options...
Sean Waters Posted April 17, 2009 Report Share Posted April 17, 2009 Re: How Long Does It Take To Fall? We also assume characters are 2m tall by default. Do we count the impact when the car hits the ground' date=' or when the car hits "head height." [/quote'] Depends on how strong the target is Quote Link to comment Share on other sites More sharing options...
PhilFleischmann Posted April 19, 2009 Report Share Posted April 19, 2009 Re: How Long Does It Take To Fall? So, 1 segment = 10 metres per second = 10 metres fallen by end of segment 2 segments =20 metres pser second = 30 metres fallen by end of segment 3 segments = 30 metres per second = 60 metres fallen by end of segment 20" is 40 metres so it hits somtime in the third segment doing between 30 and 60 metres per second (15" to 30") Not quite. It would only fall 10 meters in the first segment if it was going 10 m/s for the entire segment, but it only gets to that speed at the end of the segment. It starts (we're assuming here) with an initial velocity of 0. So it actually has only fallen 5 meters by the end of the first segment. Likewise, during the second segment, it isn't going 20 m/s the whole time. It begins the second segment with a velocity of 10 m/s and ends with 20 m/s, so it actually tavels 15 m for the second segment - a total of 20 m (10") fallen in two segments. And another 25 m in the third segment. And yes, I'm rounding earth's gravity from 9.8 m/s/s to 10 m/s/s. Quote Link to comment Share on other sites More sharing options...
Sean Waters Posted April 19, 2009 Report Share Posted April 19, 2009 Re: How Long Does It Take To Fall? Not quite. It would only fall 10 meters in the first segment if it was going 10 m/s for the entire segment, but it only gets to that speed at the end of the segment. It starts (we're assuming here) with an initial velocity of 0. So it actually has only fallen 5 meters by the end of the first segment. Likewise, during the second segment, it isn't going 20 m/s the whole time. It begins the second segment with a velocity of 10 m/s and ends with 20 m/s, so it actually tavels 15 m for the second segment - a total of 20 m (10") fallen in two segments. And another 25 m in the third segment. And yes, I'm rounding earth's gravity from 9.8 m/s/s to 10 m/s/s. You're right, but simplicity has many virtues, chief amonst them its simplicity. Quote Link to comment Share on other sites More sharing options...
prestidigitator Posted April 20, 2009 Report Share Posted April 20, 2009 Re: How Long Does It Take To Fall? Simplicity? y = (1/2) g t^2 t = sqrt(2 g y) That's simple. Honestly I don't know what kind of favor people think they're doing themselves by coming up with tables and averages and such. Nothing as simple as a nice little equation like that. Now I'm sure I'll need my Quote Link to comment Share on other sites More sharing options...
Sean Waters Posted April 21, 2009 Report Share Posted April 21, 2009 Re: How Long Does It Take To Fall? Simplicity? y = (1/2) g t^2 t = sqrt(2 g y) That's simple. Honestly I don't know what kind of favor people think they're doing themselves by coming up with tables and averages and such. Nothing as simple as a nice little equation like that. Now I'm sure I'll need my Pass the brain-spoon Quote Link to comment Share on other sites More sharing options...
Alibear Posted April 21, 2009 Report Share Posted April 21, 2009 Re: How Long Does It Take To Fall? What Sean said. Quote Link to comment Share on other sites More sharing options...
Crypt Posted April 21, 2009 Report Share Posted April 21, 2009 Re: How Long Does It Take To Fall? where is the initial velocity (m/s). is the vertical velocity with respect to time (m/s). is the initial altitude (m). is the altitude with respect to time (m). is time elapsed (s). is the acceleration due to gravity (9.81 m/s2 near the surface of the earth). http://en.wikipedia.org/wiki/Free-fall Simplicity? y = (1/2) g t^2 t = sqrt(2 g y) That's simple. Honestly I don't know what kind of favor people think they're doing themselves by coming up with tables and averages and such. Nothing as simple as a nice little equation like that. This equation only give speed at the impact. Quote Link to comment Share on other sites More sharing options...
Alibear Posted April 21, 2009 Report Share Posted April 21, 2009 Re: How Long Does It Take To Fall? Letters are for writing with not for adding together and multiplying by yet more letters. Quote Link to comment Share on other sites More sharing options...
Crypt Posted April 21, 2009 Report Share Posted April 21, 2009 Re: How Long Does It Take To Fall? Letters are for writing with not for adding together and multiplying by yet more letters. Don't you know hexadecimal ? 1AF3 + E058 = FB4B Quote Link to comment Share on other sites More sharing options...
Alibear Posted April 21, 2009 Report Share Posted April 21, 2009 Re: How Long Does It Take To Fall? Giruy! Quote Link to comment Share on other sites More sharing options...
bigbywolfe Posted April 21, 2009 Report Share Posted April 21, 2009 Re: How Long Does It Take To Fall? Don't you know hexadecimal ? 1AF3 + E058 = FB4B I know Hexadecimal! She was one of the villains on the cartoon "ReBoot", right? Quote Link to comment Share on other sites More sharing options...
Sean Waters Posted April 21, 2009 Report Share Posted April 21, 2009 Re: How Long Does It Take To Fall? I know Hexadecimal! She was one of the villains on the cartoon "ReBoot"' date=' right?[/quote'] I think so, but she seems to write numbers with letters in them, damn her. Anyway, there are only 10 kinds of people: those who understand binary and those who don't. Quote Link to comment Share on other sites More sharing options...
Doc Democracy Posted April 21, 2009 Report Share Posted April 21, 2009 Re: How Long Does It Take To Fall? Anyway' date=' there are only 10 kinds of people: those who understand binary and those who don't.[/quote'] A joke someone who didn't understand binary tried to tell me rather than show me.... Quote Link to comment Share on other sites More sharing options...
PhilFleischmann Posted April 21, 2009 Report Share Posted April 21, 2009 Re: How Long Does It Take To Fall? Letters are for writing with not for adding together and multiplying by yet more letters. Unless of course you have a high school diploma, in which case you should know more than enough basic algebra to do such simple calculations. Quote Link to comment Share on other sites More sharing options...
Sean Waters Posted April 21, 2009 Report Share Posted April 21, 2009 Re: How Long Does It Take To Fall? A joke someone who didn't understand binary tried to tell me rather than show me.... Oh that is beautiful. Quote Link to comment Share on other sites More sharing options...
Sean Waters Posted April 21, 2009 Report Share Posted April 21, 2009 Re: How Long Does It Take To Fall? Unless of course you have a high school diploma' date=' in which case you should know more than enough basic algebra to do such simple calculations.[/quote'] That depends entirely on where you got your high school diploma. The creative use of the lockpicking, stealth and PS Burglar skills are not going to multiply P and I and E. And square it. Hmmmm.......square pie....... Quote Link to comment Share on other sites More sharing options...
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