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#1
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why increasing strength doesn't (automatically) increase power
Since this comes up over and over and over again on multiple forums, I
thought I'd try to clear up some of the confusion: http://home.earthlink.net/~acoggan/misc/id4.html |
#2
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why increasing strength doesn't (automatically) increase power
Lots of technical terms there, as befits a scientific article. As is typical
in scientific literature technical terms are also misused if they sound more technical. In particular, the chart describes "circumferential pedal velocity." As far as I know, the term "velocity" describes speed and direction, so the correct term here is "speed", since the "velocity" of the pedal is constantly changing. Moreover, the word "circumferential" is redundant, given the natural assumption that pedal speed is taken with respect to the bicycle as frame of reference. -ilan "Andy Coggan" wrote in message hlink.net... Since this comes up over and over and over again on multiple forums, I thought I'd try to clear up some of the confusion: http://home.earthlink.net/~acoggan/misc/id4.html |
#3
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why increasing strength doesn't (automatically) increase power
The top-posting Ilan Vardi wrote:
Lots of technical terms there, as befits a scientific article. As is typical in scientific literature technical terms are also misused if they sound more technical. In particular, the chart describes "circumferential pedal velocity." As far as I know, the term "velocity" describes speed and direction, so the correct term here is "speed", since the "velocity" of the pedal is constantly changing. Moreover, the word "circumferential" is redundant, given the natural assumption that pedal speed is taken with respect to the bicycle as frame of reference. Conveying precise concepts requires precise use of terminology. While I agree with you that simple "pedal speed" might be sufficient should it be used within context, it might not be if, for example, the plot was presented out of context. Hence, "circumferential pedal velocity", i.e, the speed and direction that the pedal travels. Andy Coggan |
#4
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why increasing strength doesn't (automatically) increase power
On Fri, 14 Nov 2003 13:00:25 GMT, Andy Coggan wrote:
Conveying precise concepts requires precise use of terminology. While I agree with you that simple "pedal speed" might be sufficient should it be used within context, it might not be if, for example, the plot was presented out of context. Hence, "circumferential pedal velocity", i.e, the speed and direction that the pedal travels. http://home.earthlink.net/~acoggan/s...gthvspower.gif Bull****. It's a simple 2D plot, only the magnitude of the velocity is used. How can "pedal speed (m/s)" be misinterpreted?! If you want to be more precise you could say "Pedal turning speed (m/s)" or "Pedal speed wrt. axle (m/s)", but "Circumferential pedal velocity", please. I think you were just afraid of the alternative abbreviation PTS. Btw, thanks for your efforts in writing the article. |
#5
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why increasing strength doesn't (automatically) increase power
Ewoud Dronkert wrote:
On Fri, 14 Nov 2003 13:00:25 GMT, Andy Coggan wrote: Conveying precise concepts requires precise use of terminology. While I agree with you that simple "pedal speed" might be sufficient should it be used within context, it might not be if, for example, the plot was presented out of context. Hence, "circumferential pedal velocity", i.e, the speed and direction that the pedal travels. http://home.earthlink.net/~acoggan/s...gthvspower.gif Bull****. It's a simple 2D plot, only the magnitude of the velocity is used. How can "pedal speed (m/s)" be misinterpreted?! If you want to be more precise you could say "Pedal turning speed (m/s)" or "Pedal speed wrt. axle (m/s)", but "Circumferential pedal velocity", please. I think you were just afraid of the alternative abbreviation PTS. Btw, thanks for your efforts in writing the article. This is the kind of discussion that turns many people off from science and engineering. (I haven't read the paper yet but maybe a conversion to angular velocity would've created a more unassailable text?) "You call THAT punctuation?" -- -- Lynn Wallace http://www.xmission.com/~lawall "We should not march into Baghdad. ... Assigning young soldiers to a fruitless hunt for a securely entrenched dictator and condemning them to fight in what would be an unwinnable urban guerilla war, it could only plunge that part of the world into ever greater instability." George Bush Sr. in his 1998 book "A World Transformed" |
#6
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why increasing strength doesn't (automatically) increase power
Now if we can only think of a reason to abbreviate it PMS.
"Ewoud Dronkert" wrote in message l.nl... On Fri, 14 Nov 2003 13:00:25 GMT, Andy Coggan wrote: Conveying precise concepts requires precise use of terminology. While I agree with you that simple "pedal speed" might be sufficient should it be used within context, it might not be if, for example, the plot was presented out of context. Hence, "circumferential pedal velocity", i.e, the speed and direction that the pedal travels. http://home.earthlink.net/~acoggan/s...tebuilderpictu res/strengthvspower.gif Bull****. It's a simple 2D plot, only the magnitude of the velocity is used. How can "pedal speed (m/s)" be misinterpreted?! If you want to be more precise you could say "Pedal turning speed (m/s)" or "Pedal speed wrt. axle (m/s)", but "Circumferential pedal velocity", please. I think you were just afraid of the alternative abbreviation PTS. Btw, thanks for your efforts in writing the article. |
#7
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why increasing strength doesn't (automatically) increase power
"Andy Coggan" wrote in message k.net...
Conveying precise concepts requires precise use of terminology. While I agree with you that simple "pedal speed" might be sufficient should it be used within context, it might not be if, for example, the plot was presented out of context. Hence, "circumferential pedal velocity", i.e, the speed and direction that the pedal travels. It looks like my previous critique was not quite accurate. In order to make a graph of pedal velocity versus some other quantity, you would actually need to make a four dimensional plot. This is because pedal velocity, as opposed to pedal speed, is not roughly constant for a given value of the other quantity, so you must include time to make a plot. That is, you need to make a graph with respect to the scalars: speed, direction, time, quantity you used in your graph. To highlight the complication you introduce by insisting on using pedal velocity, note that the graph of the speed of a pedal rotating in a circle at constant speed consists of a single point, while the graph of its velocity is a 3-dimensional figure, a helix (this is what I was thinking of previously). Once again, I use an opportunity to differentiate myself from most scientists by admitting when I have made a mistake. -ilan |
#8
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why increasing strength doesn't (automatically) increase power
"Ilan Vardi" wrote in message
m... Once again, I use an opportunity to differentiate myself from most scientists by admitting when I have made a mistake. Once again, you use an opportunity to aggrandize yourself by making trivial criticisms. Andy Coggan |
#9
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why increasing strength doesn't (automatically) increase power
"Andy Coggan" wrote in message nk.net...
"Ilan Vardi" wrote in message m... Once again, I use an opportunity to differentiate myself from most scientists by admitting when I have made a mistake. Once again, you use an opportunity to aggrandize yourself by making trivial criticisms. Andy Coggan I am continually amazed by the capacity of scientists to defend their mistakes. How can you not admit that you were completely wrong in defending your use of the term velocity? Recall that science is a search for the truth. In that sense it is you who is more concerned with ego, since it takes precendence over objective truth. -ilan |
#10
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why increasing strength doesn't (automatically) increase power
Gee, I just love that kind of talk.
"Ilan Vardi" wrote in message m... "Andy Coggan" wrote in message k.net... Conveying precise concepts requires precise use of terminology. While I agree with you that simple "pedal speed" might be sufficient should it be used within context, it might not be if, for example, the plot was presented out of context. Hence, "circumferential pedal velocity", i.e, the speed and direction that the pedal travels. It looks like my previous critique was not quite accurate. In order to make a graph of pedal velocity versus some other quantity, you would actually need to make a four dimensional plot. This is because pedal velocity, as opposed to pedal speed, is not roughly constant for a given value of the other quantity, so you must include time to make a plot. That is, you need to make a graph with respect to the scalars: speed, direction, time, quantity you used in your graph. To highlight the complication you introduce by insisting on using pedal velocity, note that the graph of the speed of a pedal rotating in a circle at constant speed consists of a single point, while the graph of its velocity is a 3-dimensional figure, a helix (this is what I was thinking of previously). Once again, I use an opportunity to differentiate myself from most scientists by admitting when I have made a mistake. -ilan |
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