happythoughts 0 #76 January 16, 2004 Superluminaries? Isn't that another word for movie star. What if Cher was driving the car? Could she average 180? Quote Share this post Link to post Share on other sites
PhillyKev 0 #77 January 16, 2004 QuoteIt takes no time, so it would work, No it wouldn't. Light does take time to travel distances. IIRC it takes 8 minutes to get from the sun to the earth. Quote Share this post Link to post Share on other sites
happythoughts 0 #78 January 16, 2004 QuoteQuoteIt takes no time, so it would work, No it wouldn't. Light does take time to travel distances. IIRC it takes 8 minutes to get from the sun to the earth. That is just during the winter, that is why it is colder. Quote Share this post Link to post Share on other sites
Clownburner 0 #79 January 16, 2004 QuoteMost traffic lights are timed to function on an average speed of 35mph. If everyone travels at that speed, you will keep hitting green lights. Maybe where you live. In Southern California, virtually all traffic lights are timed and traffic-activated, so no matter what speed you go, you eventually hit red lights. Of course, down here, the common response to a red light is to drive through it. 7CP#1 | BTR#2 | Payaso en fuego Rodriguez "I want hot chicks in my boobies!"- McBeth Quote Share this post Link to post Share on other sites
rehmwa 2 #80 January 16, 2004 QuoteQuoteIt takes no time, so it would work, No it wouldn't. Light does take time to travel distances. IIRC it takes 8 minutes to get from the sun to the earth. Nice correction. I bet Kallend could explain it. (but could he do it without taking a potshot at some politician?) Speed of light isn't about time travel, it's more about propagation of information. But, if you can travel to the end faster than the information which shows you are too late, then you still beat the clock and average 180 mph. (Example, I'm moving directly at you from the sun at the speed of light, you hold the stop watch, when you see me leave, hit the start button. When I'm standing next to you, hit stop. Ignore the acceleration trauma I'm experiencing and whatever wierd effects I take along with me even if they do destroy the planet and, more importantly, the stop watch. I guarantee you don't show 8 minutes, but if I also have a stop watch, it does show 8 minutes.) ... Driving is a one dimensional activity - a monkey can do it - being proud of your driving abilities is like being proud of being able to put on pants Quote Share this post Link to post Share on other sites
happythoughts 0 #81 January 16, 2004 QuoteIgnore the acceleration trauma I'm experiencing That is why the "jumping up at the last moment in a falling elevator" scenario doesn't work. Exceleration stress. Quote Share this post Link to post Share on other sites
panzwami 0 #82 January 16, 2004 Actually, this would work, if you could jump in a direction opposite to the elevator's direction of travel (meaning in this case you would jump straight up), at a rate exactly equal to that at which the elevator is falling. For example, if the elevator is falling at 10 mph, and you jump straight up at 10 mph, for a short amount of time you will remain essentially stationary in space (the two vectors would momentarily cancel each other), until gravity accelerates you back down with the elevator (or you slam into the ceiling of the falling car). If you could time this jump at the exact instant the car gets to ground level, your impact would be minimal. The reason the "jump up right before the elevator hits the ground" theory isn't really feasible, is simply because if the elevator is freefalling toward the ground, there is no way you will be able to jump with enough vertical speed to counteract your fall. Thus.....splat. Matt ----- Quote Share this post Link to post Share on other sites
panzwami 0 #83 January 16, 2004 Although, the point about the acceleration stress is correct. Even if you could jump up fast enough to counter a freefalling elevator, the stress of such a massive acceleration over such a short period of time would definitely hurt a bit. Matt ----- Quote Share this post Link to post Share on other sites
happythoughts 0 #84 January 16, 2004 The elevator is going 30mph. You have to jump when it is 1 foot off the ground. In the fraction of a second that it takes the elevator to go 1 foot, you have to excelerate from zero to 30mph. The problem is that your body moves by tightening muscles to propel your bones. You bones may move, but your organs are attached by ligaments and tissue to the bones. That tissue would tear. All your organs would break loose sink to your ankles. You would look like a fisherman with leaky waders. Quote Share this post Link to post Share on other sites
kallend 1,623 #85 January 16, 2004 QuoteQuoteTraffic lights (which are an invention of Satan) have the worst possible effect on your trip time, because you are completely stationary while waiting, and the increased speed when you encounter a green one can never compensate for the time you waste at red ones. Most traffic lights are timed to function on an average speed of 35mph. If everyone travels at that speed, you will keep hitting green lights. Of course, ones that are timed for 35 are timed for 70 also. You haven't encountered "most" traffic lights. I can assure you than in Illinois there's no synchronization between lights, so there's no speed that assures you'll only see green. Manhattan (NYC) lights are nicely synchronized, though. Do you know that traffic engineering is the only branch of engineering that has no math prerequisite requirements?... The only sure way to survive a canopy collision is not to have one. Quote Share this post Link to post Share on other sites
kallend 1,623 #86 January 16, 2004 QuoteQuoteHence it doesn't matter if he goes at the speed of light, he still can't do it. (I hope you're not just being annoying). I thought she was being pert at that point . But if you go the speed of light, then does it take any time? If the guy holding the stop watch is standing at the finish line, then it doesn't take any time to complete the last bit from his perspective. (but only if it's a straight track - not likely since it's called 8 'laps') I'd already thought about that point. The centripetal acceleration would be awesome.... The only sure way to survive a canopy collision is not to have one. Quote Share this post Link to post Share on other sites
kallend 1,623 #87 January 16, 2004 QuoteQuoteBut if you go the speed of light, then does it take any time? It takes no time, so it would work, but there is one problem. Remembering that space and gravity bend light, your headlights would reach the edge of the universe and wrap around. They would then be shining in your rearview mirror, which really annoys me. I would think someone was tailgating me, have road-rage issues, start weaving while flipping that tailgater off, and wreck. So, even though the equation works for conditions where time equal zero, it just wouldn't be prudent. But he's on a track, and even at the speed of light he would take longer around the track than the time it takes to get the signal from the car to the timekeeper. Therefore it would take time.... The only sure way to survive a canopy collision is not to have one. Quote Share this post Link to post Share on other sites
kallend 1,623 #88 January 16, 2004 QuoteSee Attached Zip file (with excel and html file) to get the numbers. The solution in the attached spreadsheet assumes that the average lap time for the first 8 laps was calculated over the entire 8 laps. The max speed of the car was limited to 96mph which over 8 laps yields an average speed of 90mph (assuming the race started at 0mph). This also models an engine problem that limits the car to some arbitrary max speed. In this scenario to finish the race with an OVERALL RACE average of 180mph, our friend Schumacher would have to make his car do 281.6mph. That's my final answer. OBTW, track distance does not matter as long as the track distance stays the same throughout the race, which is ideal as autoracers usually frown upon having to slow down for construction workers. Blue Skies! -kjarv It's wrong - do it again.... The only sure way to survive a canopy collision is not to have one. Quote Share this post Link to post Share on other sites
PhillyKev 0 #89 January 16, 2004 QuoteI guarantee you don't show 8 minutes, But some time would still have passed, which still makes it not a viable solution to the initial problem. Quote Share this post Link to post Share on other sites
kallend 1,623 #90 January 16, 2004 QuoteQuoteQuoteIt takes no time, so it would work, No it wouldn't. Light does take time to travel distances. IIRC it takes 8 minutes to get from the sun to the earth. That is just during the winter, that is why it is colder. The sun is actually farther away during northern hemisphere summer. OK, who wants to explain the analemma?... The only sure way to survive a canopy collision is not to have one. Quote Share this post Link to post Share on other sites
kallend 1,623 #91 January 16, 2004 QuoteQuoteQuoteIt takes no time, so it would work, No it wouldn't. Light does take time to travel distances. IIRC it takes 8 minutes to get from the sun to the earth. Nice correction. I bet Kallend could explain it. (but could he do it without taking a potshot at some politician?) Sun --> solar energy --> energy policy -->Enron --> Ken Lay and GWB. Did I pass? ... The only sure way to survive a canopy collision is not to have one. Quote Share this post Link to post Share on other sites
PhillyKev 0 #92 January 16, 2004 QuoteOK, who wants to explain the analemma? combination of the tilt of the earth's axis in relation to the sun and eliptical orbit. Quote Share this post Link to post Share on other sites
rehmwa 2 #93 January 16, 2004 QuoteQuoteQuoteQuoteIt takes no time, so it would work, No it wouldn't. Light does take time to travel distances. IIRC it takes 8 minutes to get from the sun to the earth. Nice correction. I bet Kallend could explain it. (but could he do it without taking a potshot at some politician?) Sun --> solar energy --> energy policy -->Enron --> Ken Lay and GWB. Did I pass? ... Driving is a one dimensional activity - a monkey can do it - being proud of your driving abilities is like being proud of being able to put on pants Quote Share this post Link to post Share on other sites
kallend 1,623 #94 January 16, 2004 QuoteQuoteOK, who wants to explain the analemma? combination of the tilt of the earth's axis in relation to the sun and eliptical orbit. You get A+. When you do the math (which is actually quite tricky unless you are a whiz at spherical trig) the eccentricity of the orbit makes very little difference. The biggest effect is the tilt of the axis.... The only sure way to survive a canopy collision is not to have one. Quote Share this post Link to post Share on other sites
lawrocket 3 #95 January 16, 2004 QuoteQuoteQuoteTraffic lights (which are an invention of Satan) have the worst possible effect on your trip time, because you are completely stationary while waiting, and the increased speed when you encounter a green one can never compensate for the time you waste at red ones. Most traffic lights are timed to function on an average speed of 35mph. If everyone travels at that speed, you will keep hitting green lights. Of course, ones that are timed for 35 are timed for 70 also. You haven't encountered "most" traffic lights. I can assure you than in Illinois there's no synchronization between lights, so there's no speed that assures you'll only see green. Manhattan (NYC) lights are nicely synchronized, though. Do you know that traffic engineering is the only branch of engineering that has no math prerequisite requirements? I'm with kallend here. Why? I am well-acquainted with people in city and county governments. Here's a little snippet of knowledge for you: Governments will deliberately engineer gridlock Why? Well, they don't like to do it on rural routes, on on most roads where the traffic is designed to flow smoothly through residences and the like. However, in areas with shopping centers, strip malls and restaurants, they want traffic to stop. Ever see those places where a right turn lane -COULD- be, but is not? How about where the timing of the lights forbids anyone traveling under 65 to make it? Why? They want you to notice the shops and restaurants. That way you will be tempted to go to the shops, thereby spending money. This brings in tax revenue to the municipalities. I personally believe that road rage is not caused by rude drivers. Engineered gridlock causes much more. My wife is hotter than your wife. Quote Share this post Link to post Share on other sites
Salamander 0 #96 January 16, 2004 Quote Do you know that traffic engineering is the only branch of engineering that has no math prerequisite requirements? Then your university is either creating traffic technicians (no offense) or poorly prepared engineers. Quote However, in areas with shopping centers, strip malls and restaurants, they want traffic to stop/ Of course they want traffic to stop. Access to those facilities is the purpose of that roadway. Not designing the path so that traffic will stop is bad design. I don't see how traffic issues would be considered among the easiest engineering problems to solve. Trying to model and design according to the behaviour of millions of people is not easy. If you have ideas though... please express them. I will pass them on to the engineers that need the help. Quote Share this post Link to post Share on other sites
lawrocket 3 #97 January 16, 2004 My point is that paths that allow traffic to enter the centers without destroying the flow of other traffic are deliberately destroyed. It happened in my old hometown when they sought to redevelop a road. They eliminated right turn lanes (which previously worked fine) so that others would have to notice what was going on. The timing of the lights was changed to forestall smooth traffic flow (it is not even on demand timing at Oh Dark Thirty in the morning). Thus, the street is a mess for traffic. Knowing some people involved, they explained that the exact reason for doing it was to increase the shopping. Of course, traffic has thinned out quite a bit on that Avenue, since the locals avoid it. You'd figure they'd have thought of that. My wife is hotter than your wife. Quote Share this post Link to post Share on other sites
SkydiveNFlorida 0 #98 January 16, 2004 90m/h = Vav = change in distance / change in time... but we have no time or distance to work with here so i'm not sure how to work this problem. Ok, he finished half of the race at 90mph. So, to average 180mph it would *seem* he'd have to drive 270mph for the remainder of the race... But, this still seems unworkable because it doesn't say how long it took him to complete half of the race. We could make some assumptions and work the problem, but then it wouldn't be an accurate answer. I don't get it. Angela. Quote Share this post Link to post Share on other sites
KrisFlyZ 0 #99 January 17, 2004 Quote90m/h = Vav = change in distance / change in time... but we have no time or distance to work with here so i'm not sure how to work this problem. Ok, he finished half of the race at 90mph. So, to average 180mph it would *seem* he'd have to drive 270mph for the remainder of the race... But, this still seems unworkable because it doesn't say how long it took him to complete half of the race. We could make some assumptions and work the problem, but then it wouldn't be an accurate answer. I don't get it. Angela. The reason 270 mph came up is because of a common misconception. If you travelled for the same amount of time and two different speeds, the average speed is the sum of the speeds divided by 2. But this is just a special case and not always true. If you travelled between points A and B(distance d miles) and travelled one direction at 90 mph and the other direction at 270 mph the average speed is not 180 mph. It is 2d divided by d/90 + d/270 i.e 135 mph. Average velocity = Total distance / total time The problem is an example to illustrate what many posters(kallend first) have said; If you have covered an nth part of a fixed distance d at an average speed of w, you cannot in the remaining distance travel fast enough(lets say v) to make the total average speed n times w. Equation 1 :(d/n)*w + (n-1)*d /n*v = d/n*w this indicates that v is infinity. The equation above is the time for travelling the first nth part of the distance or the distance d divided by n at an average speed of w. (d/n)*w The remaining part or ( n-1/n ) * d at v for a time of d * (n-1)/(n*v). for the average speed to be n*w Equation 1 must be true. which says (n-1)*d /n*v = 0 or that v is Infinity. since Michael Schumacher does'nt use an Infinity he cannot do it. Quote Share this post Link to post Share on other sites
kallend 1,623 #100 January 17, 2004 Quote90m/h = Vav = change in distance / change in time... but we have no time or distance to work with here so i'm not sure how to work this problem. Ok, he finished half of the race at 90mph. So, to average 180mph it would *seem* he'd have to drive 270mph for the remainder of the race... But, this still seems unworkable because it doesn't say how long it took him to complete half of the race. We could make some assumptions and work the problem, but then it wouldn't be an accurate answer. I don't get it. Angela. It doesn't matter how long the lap is. To average 180mph he needs to complete 16 laps in a certain time, lets call it T seconds (being original). Now, to complete 1/2 of the race at 1/2 the speed also takes T seconds (the 1/2 cancels out). So he has already used up all of the T seconds just to complete 1/2 of the race. Consequently there's no possible way to complete the next 1/2 of the race in no time at all. The average speed can only be obtained by dividing total distance by total time. You can't just take the mean of the 1st half and 2nd half speeds.... The only sure way to survive a canopy collision is not to have one. Quote Share this post Link to post Share on other sites
