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YouTube - We Still Don’t Know How Bicycles Work
On 26/01/2021 02:17, Steve Weeks wrote:
On Monday, January 25, 2021 at 3:44:02 PM UTC-6, wrote: Why don't you tell us about that math that can measure the circumference of an oval? Google is your friend: the formula is PI * SquareRoot of 2 * ((1/2 long axis)squared + (1/2 short axis)squared). Or even easier: http://www.csgnetwork.com/circumelli...0axis)squared). Is that not an approximation...? |
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#12
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YouTube - We Still Don’t Know How Bicycles Work
On Monday, January 25, 2021 at 5:17:55 PM UTC-8, Steve Weeks wrote:
On Monday, January 25, 2021 at 3:44:02 PM UTC-6, wrote: Why don't you tell us about that math that can measure the circumference of an oval? Google is your friend: the formula is PI * SquareRoot of 2 * ((1/2 long axis)squared + (1/2 short axis)squared). Or even easier: http://www.csgnetwork.com/circumelli...0axis)squared). Steve, did you notice the part that said, "This calculator is designed to give the approximate circumference of any ellipse."? There is no formula for finding the circumference of an oval. Mathematics like most other sciences are limited in scope. We cannot even measure the actual orbit of the Earth after how many millennia? |
#13
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YouTube - We Still Don’t Know How Bicycles Work
On Monday, January 25, 2021 at 11:02:01 PM UTC-8, Tosspot wrote:
On 26/01/2021 02:17, Steve Weeks wrote: On Monday, January 25, 2021 at 3:44:02 PM UTC-6, wrote: Why don't you tell us about that math that can measure the circumference of an oval? Google is your friend: the formula is PI * SquareRoot of 2 * ((1/2 long axis)squared + (1/2 short axis)squared). Or even easier: http://www.csgnetwork.com/circumelli...0axis)squared). Is that not an approximation...? Well, do you remember the old TV series "Science In Action"? This was a programs in which they explained the limitations of the various sciences and that mathematics was one of the most limited of all. A couple of days ago Yahoo had an article in which a "scientist" claimed that a passing meteor was proof of an alien civilization because he couldn't calculate why the orbit accelerated in a manner that you didn't understand. Gravity assisted orbits have been used for a hundred years not to approximate the speed and direction of satellites. We presently have one that is "probably" moving into interstellar space. In another article we were told that we got alien radio signals from Proxima Centauri. This, as its name implies is the closes star to Sol and is a Red Dwarf without any known planets. That would make any difference anyway because it is so small it is bleeding most of its mass away rapidly without sufficient gravity to hold onto it which means that if there were a planet, it would be so radiated with IR that it would be red hot. We haven't observed Proxima Centauri long enough but it is probable that it is a satellite of Alpha Centauri A and B, a binary pair of slightly larger Sol type of stars. Due to these orbits no planet could form life since every 25,000 years or so it would be super-radiated with IR. This is the sort of crap that is being sold to the stupid and those without natural skepticism. The sort of thing that John and Peter gobble up. |
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YouTube - We Still Don’t Know How Bicycles Work
Steve, did you notice the part that said, "This calculator is designed to give the approximate circumference of any ellipse."? There is no formula for finding the circumference of an oval. Mathematics like most other sciences are limited in scope. We cannot even measure the actual orbit of the Earth after how many millennia? Yes, but it seems good enough for "Government Work" ;-) Sort of irritating that it says "approximate" without indicating *how* approximate. There's a more accurate formula he https://sciencing.com/calculate-circ...l-5948695.html Science may have its limitations, but it's the best tool we have for finding out how stuff works. |
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YouTube - We Still Don’t Know How Bicycles Work
On Tuesday, January 26, 2021 at 10:22:31 AM UTC-8, Steve Weeks wrote:
Steve, did you notice the part that said, "This calculator is designed to give the approximate circumference of any ellipse."? There is no formula for finding the circumference of an oval. Mathematics like most other sciences are limited in scope. We cannot even measure the actual orbit of the Earth after how many millennia? Yes, but it seems good enough for "Government Work" ;-) Sort of irritating that it says "approximate" without indicating *how* approximate. There's a more accurate formula he https://sciencing.com/calculate-circ...l-5948695.html Science may have its limitations, but it's the best tool we have for finding out how stuff works. Depending on the shape and the size of the ellipse it can range from slightly approximate to so far off you couldn't believe it. |
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YouTube - We Still Don’t Know How Bicycles Work
On Tuesday, January 26, 2021 at 10:22:31 AM UTC-8, Steve Weeks wrote:
Steve, did you notice the part that said, "This calculator is designed to give the approximate circumference of any ellipse."? There is no formula for finding the circumference of an oval. Mathematics like most other sciences are limited in scope. We cannot even measure the actual orbit of the Earth after how many millennia? Yes, but it seems good enough for "Government Work" ;-) Sort of irritating that it says "approximate" without indicating *how* approximate. There's a more accurate formula he https://sciencing.com/calculate-circ...l-5948695.html Science may have its limitations, but it's the best tool we have for finding out how stuff works. I should add that a part of what is called "man made climate change" is due almost entirely to the elliptical orbit of the Earth about the Sun and the manner of the Earth being tilted on its axis in relation to the Sun. |
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YouTube - We Still Don’t Know How Bicycles Work
Steve, did you notice the part that said, "This calculator is designed to give the approximate circumference of any ellipse."? There is no formula for finding the circumference of an oval. Mathematics like most other sciences are limited in scope. We cannot even measure the actual orbit of the Earth after how many millennia?
Yes, but it seems good enough for "Government Work" ;-) Sort of irritating that it says "approximate" without indicating *how* approximate. There's a more accurate formula he https://sciencing.com/calculate-circ...l-5948695.html Science may have its limitations, but it's the best tool we have for finding out how stuff works. First of all, "oval" is an imprecise term. Not all ovals are ellipses. A typical oval race track, for example, is not an ellipse, and it's easy to calculate its circumference. Concerning ellipses, there are absolutely exact formulas for the circumference: https://en.wikipedia.org/wiki/Ellipse#Circumference The formulas are not in simple closed form, but that doesn't mean that they don't exist, or that the problem is somehow beyond the scope of mathematics. If understanding or implementing a mathematical solution is beyond the capabilities of a particular individual, that's a different issue. |
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YouTube - We Still Don’t Know How Bicycles Work
On 1/26/2021 1:47 PM, Bertrand wrote:
Steve, did you notice the part that said, "This calculator is designed to give the approximate circumference of any ellipse."? There is no formula for finding the circumference of an oval. Mathematics like most other sciences are limited in scope. We cannot even measure the actual orbit of the Earth after how many millennia? Yes, but it seems good enough for "Government Work" ;-) Sort of irritating that it says "approximate" without indicating *how* approximate. There's a more accurate formula he https://sciencing.com/calculate-circ...l-5948695.html Science may have its limitations, but it's the best tool we have for finding out how stuff works. First of all, "oval" is an imprecise term.Â* Not all ovals are ellipses. A typical oval race track, for example, is not an ellipse, and it's easy to calculate its circumference. Concerning ellipses, there are absolutely exact formulas for the circumference: https://en.wikipedia.org/wiki/Ellipse#Circumference The formulas are not in simple closed form, but that doesn't mean that they don't exist, or that the problem is somehow beyond the scope of mathematics.Â* If understanding or implementing a mathematical solution is beyond the capabilities of a particular individual, that's a different issue. Let me add that my ancient bound copy of _Standard Handbook for Mechanical Engineers_ (AKA Marks' Handbook) has on page 2-18 "Length of perimeter of ellipse..." followed by three pretty simple formulas. The trick is, the equation defining one constant K is a converging infinite series. The Handbook doesn't even blink an eye at this, figuratively speaking. In practice, you simply evaluate K using as many terms as necessary to generate the accuracy you need. This is perfectly acceptable, because in the real physical world nothing is measured or manufactured to absolute perfection. However, infinite series may be incomprehensible to those with, shall we say, limited education. I imagine the concept of Pi must also be baffling to those people. ("You mean it goes on forever??? That means we don't know it's value!!!") -- - Frank Krygowski |
#19
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YouTube - We Still Don’t Know How Bicycles Work
On 1/26/2021 12:29 PM, Tom Kunich wrote:
On Tuesday, January 26, 2021 at 10:22:31 AM UTC-8, Steve Weeks wrote: Steve, did you notice the part that said, "This calculator is designed to give the approximate circumference of any ellipse."? There is no formula for finding the circumference of an oval. Mathematics like most other sciences are limited in scope. We cannot even measure the actual orbit of the Earth after how many millennia? Yes, but it seems good enough for "Government Work" ;-) Sort of irritating that it says "approximate" without indicating *how* approximate. There's a more accurate formula he https://sciencing.com/calculate-circ...l-5948695.html Science may have its limitations, but it's the best tool we have for finding out how stuff works. I should add that a part of what is called "man made climate change" is due almost entirely to the elliptical orbit of the Earth about the Sun and the manner of the Earth being tilted on its axis in relation to the Sun. First you wrote 'oval' meaning 'ellipse'. Those are different things (ellipses being a small subset of ovals) in terms of Euclidean geometry. I don't know what you mean by orbit but it's surely not an actual ellipse. -- Andrew Muzi www.yellowjersey.org/ Open every day since 1 April, 1971 |
#20
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YouTube - We Still Don’t Know How Bicycles Work
On 1/26/2021 1:39 PM, Frank Krygowski wrote:
On 1/26/2021 1:47 PM, Bertrand wrote: Steve, did you notice the part that said, "This calculator is designed to give the approximate circumference of any ellipse."? There is no formula for finding the circumference of an oval. Mathematics like most other sciences are limited in scope. We cannot even measure the actual orbit of the Earth after how many millennia? Yes, but it seems good enough for "Government Work" ;-) Sort of irritating that it says "approximate" without indicating *how* approximate. There's a more accurate formula he https://sciencing.com/calculate-circ...l-5948695.html Science may have its limitations, but it's the best tool we have for finding out how stuff works. First of all, "oval" is an imprecise term. Not all ovals are ellipses. A typical oval race track, for example, is not an ellipse, and it's easy to calculate its circumference. Concerning ellipses, there are absolutely exact formulas for the circumference: https://en.wikipedia.org/wiki/Ellipse#Circumference The formulas are not in simple closed form, but that doesn't mean that they don't exist, or that the problem is somehow beyond the scope of mathematics. If understanding or implementing a mathematical solution is beyond the capabilities of a particular individual, that's a different issue. Let me add that my ancient bound copy of _Standard Handbook for Mechanical Engineers_ (AKA Marks' Handbook) has on page 2-18 "Length of perimeter of ellipse..." followed by three pretty simple formulas. The trick is, the equation defining one constant K is a converging infinite series. The Handbook doesn't even blink an eye at this, figuratively speaking. In practice, you simply evaluate K using as many terms as necessary to generate the accuracy you need. This is perfectly acceptable, because in the real physical world nothing is measured or manufactured to absolute perfection. However, infinite series may be incomprehensible to those with, shall we say, limited education. I imagine the concept of Pi must also be baffling to those people. ("You mean it goes on forever??? That means we don't know it's value!!!") Well then, you're not approaching the problem correctly! https://rationalwiki.org/wiki/Indiana_Pi_Bill -- Andrew Muzi www.yellowjersey.org/ Open every day since 1 April, 1971 |
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