Calling all you math heads, answer me this!
Jun 6, 2006 | 03:26 PM
#101
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From: Land of the misfit toys
Calling all you math heads, answer me this!
Now that that's solved, how about if they both crossed the finish line at the same time and figure stopping distance. [img]i/expressions/face-icon-small-tongue.gif[/img]
Jun 6, 2006 | 07:15 PM
#102
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Calling all you math heads, answer me this!
Originally posted by: Knutz
That sure looks down to the foot to me.
You did not use the time for the last 66' to calculate the speed, the speed was given in the word problem. The issue arises in the fact that drag racing trap speeds are calculated this way, hence the are simply an average speed over that distance, not taking acceleration into account. It's just one more factor that makes a true answer impossible to achieve, only an approximation.
Now, if you could get into the computer and get the exact time that it entered the "traps" and the exact time it exited, your approximation would be much closer. Unfortunatly, we have no times at all for the dragster, and no sure way to get them, so a close guess is as close as anyone could come.
*edit* I went back and noticed that the top fuel record time was added to the original post, so I stand corrected about no times at all. Still, without supporting times such as reaction times, it's still a guess.
Originally posted by: BryceGTX
t = 4.31348 seconds is when the dragster passes the Nascar
S = 0.05555 * t = 0.2396 mile = 1265 feet
Bryce
t = 4.31348 seconds is when the dragster passes the Nascar
S = 0.05555 * t = 0.2396 mile = 1265 feet
Bryce
You did not use the time for the last 66' to calculate the speed, the speed was given in the word problem. The issue arises in the fact that drag racing trap speeds are calculated this way, hence the are simply an average speed over that distance, not taking acceleration into account. It's just one more factor that makes a true answer impossible to achieve, only an approximation.
Now, if you could get into the computer and get the exact time that it entered the "traps" and the exact time it exited, your approximation would be much closer. Unfortunatly, we have no times at all for the dragster, and no sure way to get them, so a close guess is as close as anyone could come.
*edit* I went back and noticed that the top fuel record time was added to the original post, so I stand corrected about no times at all. Still, without supporting times such as reaction times, it's still a guess.
So if you do not want an answer to this math problem down to the foot.. what is appropriate? Round to 10 feet?
And no.. it is not a guess. It is accurate to some degree of accuracy. When we launch a space capsule, we do not say that the orbit will be exactly blah.. blah.. blah.. Its orbit can be predicted mathematically to some degree of accuracy. As you add more information to the math problem in this thread, the prediction will be more and more accurate to real life. But to come out and say why bother to calculate because you are always wrong... We would still be riding horses if we all thought that way.
The next time we put this engine on a dynamometer, remember that the HP you measure at the wheels is not exact!! The torque transducer is only accurate to 0.1% over time and temperature. That dyno will never represent the load on the fueler as it is going down the strip. Non-the-less everyone uses dynoes to test engines. Heck, even the time measurement at the strip has a certain degree of accuracy. I guess since we know that it is incorrect, we should not use it.
Jun 6, 2006 | 07:24 PM
#105
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From: The Asphalt Jungle
Calling all you math heads, answer me this!
Originally posted by: DragonDJ11
The title of this thread is killing me.....I keep reading MATH with an "E".......
The title of this thread is killing me.....I keep reading MATH with an "E".......
Jun 6, 2006 | 07:28 PM
#106
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Calling all you math heads, answer me this!
Originally posted by: OneFlyCowboy
--------------------------------Top-Fuel-Dragster
--------Time-SC Dist----Distance-ft/sec-Speed-mph
---------3.05---894.67--660.00--393.07--268.00
---------3.10---909.33--680.10--402.05--274.13
---------3.15---924.00--700.65--411.03--280.25
---------3.20---938.67--721.66--420.02--286.38
---------3.25---953.33--743.11--429.00--292.50
---------3.30---968.00--765.00--437.98--298.63
---------3.35---982.67--787.35--446.97--304.75
---------3.40---997.33--810.15--455.95--310.88
---------3.45--1012.00--833.40--464.93--317.00
---------3.50--1026.67--857.09--473.92--323.13
---------3.55--1041.33--881.24--482.90--329.25
---------3.60--1056.00--905.89--493.02--336.15
---------3.65--1070.67--930.54--493.02--336.15
---------3.70--1085.33--955.19--493.02--336.15
---------3.75--1100.00--979.84--493.00--336.15
---------3.80--1114.67-1004.49--493.00--336.15
---------3.85--1129.33-1029.14--493.00--336.15
---------3.90--1144.00-1053.79--493.00--336.15
---------3.95--1158.67-1078.44--493.00--336.15
---------4.00--1173.33-1103.09--493.00--336.15
---------4.05--1188.00-1127.74--493.00--336.15
---------4.10--1202.67-1152.39--493.00--336.15
---------4.15--1217.33-1177.04--493.00--336.15
---------4.20--1232.00-1201.69--493.00--336.15
---------4.25--1246.67-1226.34--493.00--336.15
---------4.30--1261.33-1250.99--493.00--336.15
---------4.35--1276.00-1275.64--493.00--336.15
--------4.351--1276.29-1276.13--493.00--336.15
--------4.352--1276.59-1276.63--493.00--336.15
--------4.353--1276.88-1277.12--493.00--336.15
--------4.354--1277.17-1277.61--493.00--336.15
--------4.355--1277.47-1278.11--493.00--336.15
--------4.356--1277.76-1278.60--493.00--336.15
--------4.357--1278.05-1279.09--493.00--336.15
--------4.358--1278.35-1279.58--493.00--336.15
--------4.359--1278.64-1280.08--493.00--336.15
---------4.36--1278.93-1280.57--493.00--336.15
---------4.37--1281.87-1285.50--493.00--336.15
---------4.38--1284.80-1290.43--493.00--336.15
---------4.39--1287.73-1295.36--493.00--336.15
---------4.40--1290.67-1300.29--493.00--336.15
---------4.41--1293.60-1305.22--493.00--336.15
---------4.42--1296.53-1310.15--493.00--336.15
---------4.43--1299.47-1315.08--493.00--336.15
---------4.44--1302.40-1320.00--493.00--336.15
---------4.45--1305.33
---------4.50--1320.00
Originally posted by: Knutz
What is the amount of time to accelerate from 268 to 336, and how did you get that time?
The car doesn't travel faster than the top speed, but the simple formulations used, assume that it's doing 302MPH at 3/16th of a mile, when it likely is not. Due to the downward curve of acceleration at that point, it's actually traveling faster than the 302MPH assumed.
*edit* If we want to talk reality, the reported top speed of the car is not the actuall top speed, but an average speed for the last 66'. So it actually enters the traps at one speed, exits at another due to acceleration, and an average of the two is what's reported. It is done this way because it's the most acurate way to measure the speed at the finish, but is not 100% correct. It is close enough for racing purposes though, and since all drag races are measured this way, it offers a standard basis for compairison.
Originally posted by: OneFlyCowboy
yup thats me [img]i/expressions/face-icon-small-happy.gif[/img] and in order for the distances to be covered in the amount of time available and accelerate from the 268 to the 336 certain things have to take place.. Now if you tell me that the car actually travels faster than the top speed at the end of thetrack. well then i could be wrong.
yup thats me [img]i/expressions/face-icon-small-happy.gif[/img] and in order for the distances to be covered in the amount of time available and accelerate from the 268 to the 336 certain things have to take place.. Now if you tell me that the car actually travels faster than the top speed at the end of thetrack. well then i could be wrong.
The car doesn't travel faster than the top speed, but the simple formulations used, assume that it's doing 302MPH at 3/16th of a mile, when it likely is not. Due to the downward curve of acceleration at that point, it's actually traveling faster than the 302MPH assumed.
*edit* If we want to talk reality, the reported top speed of the car is not the actuall top speed, but an average speed for the last 66'. So it actually enters the traps at one speed, exits at another due to acceleration, and an average of the two is what's reported. It is done this way because it's the most acurate way to measure the speed at the finish, but is not 100% correct. It is close enough for racing purposes though, and since all drag races are measured this way, it offers a standard basis for compairison.
--------------------------------Top-Fuel-Dragster
--------Time-SC Dist----Distance-ft/sec-Speed-mph
---------3.05---894.67--660.00--393.07--268.00
---------3.10---909.33--680.10--402.05--274.13
---------3.15---924.00--700.65--411.03--280.25
---------3.20---938.67--721.66--420.02--286.38
---------3.25---953.33--743.11--429.00--292.50
---------3.30---968.00--765.00--437.98--298.63
---------3.35---982.67--787.35--446.97--304.75
---------3.40---997.33--810.15--455.95--310.88
---------3.45--1012.00--833.40--464.93--317.00
---------3.50--1026.67--857.09--473.92--323.13
---------3.55--1041.33--881.24--482.90--329.25
---------3.60--1056.00--905.89--493.02--336.15
---------3.65--1070.67--930.54--493.02--336.15
---------3.70--1085.33--955.19--493.02--336.15
---------3.75--1100.00--979.84--493.00--336.15
---------3.80--1114.67-1004.49--493.00--336.15
---------3.85--1129.33-1029.14--493.00--336.15
---------3.90--1144.00-1053.79--493.00--336.15
---------3.95--1158.67-1078.44--493.00--336.15
---------4.00--1173.33-1103.09--493.00--336.15
---------4.05--1188.00-1127.74--493.00--336.15
---------4.10--1202.67-1152.39--493.00--336.15
---------4.15--1217.33-1177.04--493.00--336.15
---------4.20--1232.00-1201.69--493.00--336.15
---------4.25--1246.67-1226.34--493.00--336.15
---------4.30--1261.33-1250.99--493.00--336.15
---------4.35--1276.00-1275.64--493.00--336.15
--------4.351--1276.29-1276.13--493.00--336.15
--------4.352--1276.59-1276.63--493.00--336.15
--------4.353--1276.88-1277.12--493.00--336.15
--------4.354--1277.17-1277.61--493.00--336.15
--------4.355--1277.47-1278.11--493.00--336.15
--------4.356--1277.76-1278.60--493.00--336.15
--------4.357--1278.05-1279.09--493.00--336.15
--------4.358--1278.35-1279.58--493.00--336.15
--------4.359--1278.64-1280.08--493.00--336.15
---------4.36--1278.93-1280.57--493.00--336.15
---------4.37--1281.87-1285.50--493.00--336.15
---------4.38--1284.80-1290.43--493.00--336.15
---------4.39--1287.73-1295.36--493.00--336.15
---------4.40--1290.67-1300.29--493.00--336.15
---------4.41--1293.60-1305.22--493.00--336.15
---------4.42--1296.53-1310.15--493.00--336.15
---------4.43--1299.47-1315.08--493.00--336.15
---------4.44--1302.40-1320.00--493.00--336.15
---------4.45--1305.33
---------4.50--1320.00
Now even if that were in the word problem, your #'s are still flawed. They are based on linier acceleration. According to your formula, the dragster has topped out at the 905' mark and does no accelerating from there to the finish! I have to say, Bryce has a far better concept of how things are working and how the math must be calculated. Your assumptions are so far off that they aren't even on the same track(race track that is[img]i/expressions/face-icon-small-wink.gif[/img]). Bryce used good research and logical thought tracks to get close, even though the lack of info crippled his efforts. Look back through his posts, and you'll see how you got so far off.
Jun 6, 2006 | 07:42 PM
#107
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From: The Asphalt Jungle
Calling all you math heads, answer me this!
Originally posted by: Knutz
Impresive list of #'s. One problem though, were did you get that the dragster is hitting the 1/8th in 3.05 seconds? It's not in the original or the edited word problem. Without that being factual, the rest is based on an assumption.
Now even if that were in the word problem, your #'s are still flawed. They are based on linier acceleration. According to your formula, the dragster has topped out at the 905' mark and does no accelerating from there to the finish! I have to say, Bryce has a far better concept of how things are working and how the math must be calculated. Your assumptions are so far off that they aren't even on the same track(race track that is[img]i/expressions/face-icon-small-wink.gif[/img]). Bryce used good research and logical thought tracks to get close, even though the lack of info crippled his efforts. Look back through his posts, and you'll see how you got so far off.
Impresive list of #'s. One problem though, were did you get that the dragster is hitting the 1/8th in 3.05 seconds? It's not in the original or the edited word problem. Without that being factual, the rest is based on an assumption.
Now even if that were in the word problem, your #'s are still flawed. They are based on linier acceleration. According to your formula, the dragster has topped out at the 905' mark and does no accelerating from there to the finish! I have to say, Bryce has a far better concept of how things are working and how the math must be calculated. Your assumptions are so far off that they aren't even on the same track(race track that is[img]i/expressions/face-icon-small-wink.gif[/img]). Bryce used good research and logical thought tracks to get close, even though the lack of info crippled his efforts. Look back through his posts, and you'll see how you got so far off.
here is the run Schumacher run Im using as comparison. Certain things have to happen to make it work.
Dist-----60------330------660----1000----1320
Time---0.85---2.123---3.052---3.837---4.515
Speed------------------270.51------------325.96
Jun 6, 2006 | 07:57 PM
#108
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Calling all you math heads, answer me this!
Originally posted by: BryceGTX
And no.. it is not a guess. It is accurate to some degree of accuracy. When we launch a space capsule, we do not say that the orbit will be exactly blah.. blah.. blah.. Its orbit can be predicted mathematically to some degree of accuracy. As you add more information to the math problem in this thread, the prediction will be more and more accurate to real life. But to come out and say why bother to calculate because you are always wrong... We would still be riding horses if we all thought that way.
The next time we put this engine on a dynamometer, remember that the HP you measure at the wheels is not exact!! The torque transducer is only accurate to 0.1% over time and temperature. That dyno will never represent the load on the fueler as it is going down the strip. Non-the-less everyone uses dynoes to test engines. Heck, even the time measurement at the strip has a certain degree of accuracy. I guess since we know that it is incorrect, we should not use it.
And no.. it is not a guess. It is accurate to some degree of accuracy. When we launch a space capsule, we do not say that the orbit will be exactly blah.. blah.. blah.. Its orbit can be predicted mathematically to some degree of accuracy. As you add more information to the math problem in this thread, the prediction will be more and more accurate to real life. But to come out and say why bother to calculate because you are always wrong... We would still be riding horses if we all thought that way.
The next time we put this engine on a dynamometer, remember that the HP you measure at the wheels is not exact!! The torque transducer is only accurate to 0.1% over time and temperature. That dyno will never represent the load on the fueler as it is going down the strip. Non-the-less everyone uses dynoes to test engines. Heck, even the time measurement at the strip has a certain degree of accuracy. I guess since we know that it is incorrect, we should not use it.
Funny that you would bring up the subject of a chassis dyno being correct. Your right, a chassis dyno is nothing but an approximation. While developing the dyno, the engineers could not get the math to equal the reality. To solve the problem, it was ordered that the mathmatical formula be "fudged" so that a Yamaha V-Max motorcycle would come out as accurate and all other formula's were based on that "fudged" math. (This is a true fact) The intent is the same as I explained about the trap speeds in drag racing. They may not be accurate, but if everyone uses the same method of approximation, the information will be sufficent for compairison. That is why differing dyno's give different #'s, but if you compair results from the same dyno, you'll have a decent approximation.
Your right, if you add more information the accuracy will increase. If you make assuptions, your not adding more information, your simply guessing.
Jun 6, 2006 | 08:05 PM
#109
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Calling all you math heads, answer me this!
Cowboy, you are so far off that we would have to go back to high school algebra to get you back on track. I don't say this to be insulting, but you would have to follow Bryce's formulation to understand the error of yours.
Think about it this way, it's gaining speed all the way through the run. It's just not gaining it as quickly at the end of the run as it is in the beginning.
Think about it this way, it's gaining speed all the way through the run. It's just not gaining it as quickly at the end of the run as it is in the beginning.
Jun 6, 2006 | 08:13 PM
#110
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Calling all you math heads, answer me this!
Would it make more sence to some people if you say its a ratio not a fixed number. Like putting bigger tires on your truck and your spedometer goes off more and more as you increase in speed. With the top fuel car the rate of acceleration is delivered on a ratio over distance.
