Nothing to do with programming : question for physicits
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Hi ! I have a question about physics, and I though maybe someone from the CP community might be able to help me : Let's imagine a train, following a railway. The train has a speed S and arrives with this speed in a turn (of a given radius R). If the mass of the train is important, let's say it's mass is M. How can I calculate at which speed, the train will be too fast and will leave the rail ???? And, maybe the train won't leave the rail immediately at the beginning of the turn, but, let's say, somewhere in the middle of the turn. How can I calculate this position where the train will leave the rail ? Thank you !!! Jerome
For one thing your going to need to know the centre of gravity of the train. Also are you assuming that if one carrige goes the others go, which in real life would not be the case? This can be easily investigated by looking at a cross section of a train. First look at this from the point of view of a train at rest, where someone is trying to push it over by hand - not likey either. You need to know the vertical acceleration (gravity - not hard) and the lateral force ( this will later come from going around the corner at speed), along with the centre of gravity. You can work out the horizontal force required to tip the train over at rest, by combining the two force vectors until they are outside the wheel base - at which point the train will start to tip. The acceleration from going around a bend is (me thinks - been a while) acceleration = angular velocity * radius Once the acceleration from going around the bend surpases the at rest push over acceleration then your there. And if that make sense then god help you. :laugh: Quote from a clever bloke : "I know not with what weapons World War III will be fought, but World War IV will be fought with sticks and stones." - Albert Einstein
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Hi ! I have a question about physics, and I though maybe someone from the CP community might be able to help me : Let's imagine a train, following a railway. The train has a speed S and arrives with this speed in a turn (of a given radius R). If the mass of the train is important, let's say it's mass is M. How can I calculate at which speed, the train will be too fast and will leave the rail ???? And, maybe the train won't leave the rail immediately at the beginning of the turn, but, let's say, somewhere in the middle of the turn. How can I calculate this position where the train will leave the rail ? Thank you !!! Jerome
What is the height of each vagon (actually where is the mass center) and what is the distance between the 2 rails? I think a vagon leaves the rail when it slope to the point that it's mass center goes outside the rails. :) One idea is to devide the vector of the speed into 2 perpendicular vectors, one pointing to the direction of the rails. The other vector whould be the power that 'push' the vagon outside the rail. - - - - - - - - - - - - - - - - - - Memory leaks is the price we pay \0 01234567890123456789012345678901234
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Paul Watson wrote: location of Biggs at the time and how much money is on the train. :-D Roger Allen Sonork 100.10016 Were you different as a kid? Did you ever say "Ooohhh, shiny red" even once? - Paul Watson 11-February-2003
Roger Allen wrote: and how much money is on the train Eeeeeeeeexactly. :-D
Paul Watson
Bluegrass
Cape Town, South AfricaMacbeth muttered: I am in blood / Stepped in so far, that should I wade no more, / Returning were as tedious as go o'er Want a job?
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Wait... my divine knowledge of celestial parephenalia tell me that... wait... wait... wait... this is a homework question! If it is not then my apologies, but it reeks of it and is no better than a programming homework question. And I don't know the answer. Surely you need more info though. Rail depth, depth of groove in train wheels, is Fat Bastard on the train, location of Biggs at the time etc. etc.
Paul Watson
Bluegrass
Cape Town, South AfricaMacbeth muttered: I am in blood / Stepped in so far, that should I wade no more, / Returning were as tedious as go o'er Want a job?
Paul Watson wrote: Surely you need more info though. Rail depth, depth of groove in train wheels, is Fat Bastard on the train, location of Biggs at the time etc. etc. Along with the average width of a horse's posterior as a constant, for validating the proper width of rail placement... Chistopher Duncan Author - The Career Programmer: Guerilla Tactics for an Imperfect World (Apress)
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What is the height of each vagon (actually where is the mass center) and what is the distance between the 2 rails? I think a vagon leaves the rail when it slope to the point that it's mass center goes outside the rails. :) One idea is to devide the vector of the speed into 2 perpendicular vectors, one pointing to the direction of the rails. The other vector whould be the power that 'push' the vagon outside the rail. - - - - - - - - - - - - - - - - - - Memory leaks is the price we pay \0 01234567890123456789012345678901234
Kastellanos Nikos wrote: What is the height of each vagon And how bad is the poetry? Oh. Sorry. Thought that was Vogon... Chistopher Duncan Author - The Career Programmer: Guerilla Tactics for an Imperfect World (Apress)
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LOL :laugh: I agree this looks like a homework assignment ;P Weiye, Chen When pursuing your dreams, don't forget to enjoy your life...
Weiye Chen wrote: looks like a homework assignment Come on guys....I finished my studies 7 years ago, this has nothing to do with homework.... But I agree that if, by that time, I would have be keener at doing my homeworks, I wouldn't be posting this question today !!! ;-) Jerome
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Hi ! I have a question about physics, and I though maybe someone from the CP community might be able to help me : Let's imagine a train, following a railway. The train has a speed S and arrives with this speed in a turn (of a given radius R). If the mass of the train is important, let's say it's mass is M. How can I calculate at which speed, the train will be too fast and will leave the rail ???? And, maybe the train won't leave the rail immediately at the beginning of the turn, but, let's say, somewhere in the middle of the turn. How can I calculate this position where the train will leave the rail ? Thank you !!! Jerome
What? A physics question in the lounge?!? You'd be better off in the Visual Physics++ forum, or perhaps the Physics.NET forum ;P -- Help me! I'm turning into a grapefruit!
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What? A physics question in the lounge?!? You'd be better off in the Visual Physics++ forum, or perhaps the Physics.NET forum ;P -- Help me! I'm turning into a grapefruit!
benjymous wrote: Physics.NET forum A train derailment hypothesis is not safe code so would need the appropriate markings in .NET. VP++ is probably the better language.
Paul Watson
Bluegrass
Cape Town, South AfricaMacbeth muttered: I am in blood / Stepped in so far, that should I wade no more, / Returning were as tedious as go o'er Want a job?
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Wait... my divine knowledge of celestial parephenalia tell me that... wait... wait... wait... this is a homework question! If it is not then my apologies, but it reeks of it and is no better than a programming homework question. And I don't know the answer. Surely you need more info though. Rail depth, depth of groove in train wheels, is Fat Bastard on the train, location of Biggs at the time etc. etc.
Paul Watson
Bluegrass
Cape Town, South AfricaMacbeth muttered: I am in blood / Stepped in so far, that should I wade no more, / Returning were as tedious as go o'er Want a job?
Paul Watson wrote: Wait... my divine knowledge of celestial parephenalia tell me that... wait... wait... wait... this is a homework question! If it is not then my apologies, but it reeks of it and is no better than a programming homework question. I admit that my question smelled like homework, but after a quick look at my profile you would have notice that studies are now several years behind me :-) But thank you for pointing out that my question was lacking important informations about Fat Bastard and Biggs ! ;-) Jerome
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benjymous wrote: Physics.NET forum A train derailment hypothesis is not safe code so would need the appropriate markings in .NET. VP++ is probably the better language.
Paul Watson
Bluegrass
Cape Town, South AfricaMacbeth muttered: I am in blood / Stepped in so far, that should I wade no more, / Returning were as tedious as go o'er Want a job?
And of course Visual High School Physics is worth avoiding like the plague, as it teaches you rubbish like the atom being the smallest datatype. It's perfectly good as a learning language though -- Help me! I'm turning into a grapefruit!
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Paul Watson wrote: Wait... my divine knowledge of celestial parephenalia tell me that... wait... wait... wait... this is a homework question! If it is not then my apologies, but it reeks of it and is no better than a programming homework question. I admit that my question smelled like homework, but after a quick look at my profile you would have notice that studies are now several years behind me :-) But thank you for pointing out that my question was lacking important informations about Fat Bastard and Biggs ! ;-) Jerome
Jerome Conus wrote: I admit that my question smelled like homework, but after a quick look at my profile you would have notice that studies are now several years behind me But thank you for pointing out that my question was lacking important informations about Fat Bastard and Biggs Jeeesh, giving me something to work with here. Now I have to post a stupid reply admiting I can't figure out how to argue with you any further. Throw me a frikin bone man! :rolleyes: Oh, and we should never stop learning. Plenty of guys here in their 50s who are doing part time course at Uni.
Paul Watson
Bluegrass
Cape Town, South AfricaMacbeth muttered: I am in blood / Stepped in so far, that should I wade no more, / Returning were as tedious as go o'er Want a job?
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And of course Visual High School Physics is worth avoiding like the plague, as it teaches you rubbish like the atom being the smallest datatype. It's perfectly good as a learning language though -- Help me! I'm turning into a grapefruit!
benjymous wrote: as it teaches you rubbish like the atom being the smallest datatype. Well, it doesn't get any better at University level either. Then you're taught that strings are the smallest datatypes! :omg: Sheesh. I wonder if I get a Nobel prize if I do some research on
char? :cool: -- I'm coming out of the closet: I :love: VB -
Paul Watson wrote: Surely you need more info though. Rail depth, depth of groove in train wheels, is Fat Bastard on the train, location of Biggs at the time etc. etc. Along with the average width of a horse's posterior as a constant, for validating the proper width of rail placement... Chistopher Duncan Author - The Career Programmer: Guerilla Tactics for an Imperfect World (Apress)
Christopher Duncan wrote: Along with the average width of a horse's posterior as a constant, for validating the proper width of rail placement... No kidding : the width of a horse is VERY important !!! :-) Did you know that the width of a horse's posterior is the origin of the size of the booster rockets of the Space Shuttle ??? In english : http://info.mountains.net.au/rail/horse-ass.htm[^] For french speakers : http://lwdr.free.fr/disjonctes.html#L'ESPACEMENT%20D'UN%20CUL%20DE%20CHEVAL[^] Jerome
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Kastellanos Nikos wrote: What is the height of each vagon And how bad is the poetry? Oh. Sorry. Thought that was Vogon... Chistopher Duncan Author - The Career Programmer: Guerilla Tactics for an Imperfect World (Apress)
Christopher Duncan wrote: And how bad is the poetry? Oh. Sorry. Thought that was Vogon... uh, those greek QCERTY-type keyboards. They make you do all sort of strange mistakes... ;P - - - - - - - - - - - - - - - - - - Memory leaks is the price we pay \0 01234567890123456789012345678901234
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Christopher Duncan wrote: And how bad is the poetry? Oh. Sorry. Thought that was Vogon... uh, those greek QCERTY-type keyboards. They make you do all sort of strange mistakes... ;P - - - - - - - - - - - - - - - - - - Memory leaks is the price we pay \0 01234567890123456789012345678901234
Kastellanos Nikos wrote: uh, those greek QCERTY-type keyboards. So you are programming in W++, right? :)
powerful binary resource reuse - another word for "no sources, you are stuck with a pain-in-the-a## COM component"
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Hi ! I have a question about physics, and I though maybe someone from the CP community might be able to help me : Let's imagine a train, following a railway. The train has a speed S and arrives with this speed in a turn (of a given radius R). If the mass of the train is important, let's say it's mass is M. How can I calculate at which speed, the train will be too fast and will leave the rail ???? And, maybe the train won't leave the rail immediately at the beginning of the turn, but, let's say, somewhere in the middle of the turn. How can I calculate this position where the train will leave the rail ? Thank you !!! Jerome
With a bit of work you can probably get it down to 50 variables: Centre of gravity of train Camber of rails Amount of oil/grease/dirt on rails etc..... Elaine :rolleyes: The tigress is here :-D
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Hi ! I have a question about physics, and I though maybe someone from the CP community might be able to help me : Let's imagine a train, following a railway. The train has a speed S and arrives with this speed in a turn (of a given radius R). If the mass of the train is important, let's say it's mass is M. How can I calculate at which speed, the train will be too fast and will leave the rail ???? And, maybe the train won't leave the rail immediately at the beginning of the turn, but, let's say, somewhere in the middle of the turn. How can I calculate this position where the train will leave the rail ? Thank you !!! Jerome
The mass in this case is unimportant; the radius of the turn and the location of the center of mass are critical. The outer rail in the turn forms a constrained pivot point, while the inner is unconstrained. The line between the outer rail and the center of mass lies at an angle, Ø, with respect to the horizontal, so the gravitational acceleration can be resolved into a tangential component (directed inward) and a radial component (directed along the line toward the rail), both acting as though applied at the center of mass. The centripetal acceleration is horizontal, acting also through the center of mass, and can be resolved into a tangential component (directed outward) and a radial component (directed upward). This centripetal acceleration is given by ac = S2/R. The speed, Sc, at which the tangential acceleration due to gravity equals the tangential acceleration due to turning is critical. Any higher speed will cause the center of mass to be accelerated toward the outside of the turn, eventually causing the train to tip, as the net tangential acceleration will be toward the outside of the turn. Once the center of mass crosses the line of the outside rail, gravitational force alone will be sufficient to drop the train to the siding. Determining the point at which this occurs requires the mass, M, to be known, as the net tangential acceleration (resolved back into a horizontal component) will create a force directed sideways to move the center of mass the width of a horse's ass and beyond the balance point directly over the outer rail. The time required to accomplish this can be calculated, and yields the point on the curve's circumference where the train is inevitably doomed. The solution details are trivial, and are, as usual, left as an exercise for the student. :) It is ok for women not to like sports, so long as they nod in the right places and bring beers at the right times.
Paul Watson, on Sports - 2/10/2003 -
Hi ! I have a question about physics, and I though maybe someone from the CP community might be able to help me : Let's imagine a train, following a railway. The train has a speed S and arrives with this speed in a turn (of a given radius R). If the mass of the train is important, let's say it's mass is M. How can I calculate at which speed, the train will be too fast and will leave the rail ???? And, maybe the train won't leave the rail immediately at the beginning of the turn, but, let's say, somewhere in the middle of the turn. How can I calculate this position where the train will leave the rail ? Thank you !!! Jerome
Jerome Conus wrote: How can I calculate this position where the train will leave the rail ? It depends on how drunk the driver is. :)
There are only 10 kind of people in the world: those who understand binary and those who don't.
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Christopher Duncan wrote: Along with the average width of a horse's posterior as a constant, for validating the proper width of rail placement... No kidding : the width of a horse is VERY important !!! :-) Did you know that the width of a horse's posterior is the origin of the size of the booster rockets of the Space Shuttle ??? In english : http://info.mountains.net.au/rail/horse-ass.htm[^] For french speakers : http://lwdr.free.fr/disjonctes.html#L'ESPACEMENT%20D'UN%20CUL%20DE%20CHEVAL[^] Jerome
The original comment apparently needed a smiley: http://www.snopes.com/history/american/gauge.htm -- Eric Move along, nothing to see here.
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With a bit of work you can probably get it down to 50 variables: Centre of gravity of train Camber of rails Amount of oil/grease/dirt on rails etc..... Elaine :rolleyes: The tigress is here :-D
Trollslayer wrote: etc..... and a cook, that is really an undercover navy seal. ;P O no, thats for a boat! MyDUMeter: a .NET DUMeter clone
"Thats like saying "hahahaha he doesnt know the difference between a cyberneticradioactivenuclothermolopticdimswitch and a biocontainingspherogramotron", but with words you have really never heard of."