版主: norman
不，你弄錯一件事，這個動作我並未模仿誰的，這是我為了加強要練一個伸縮動作的彈性及一個很特別的動作而去想出這個方法練的。pku 寫:你是模仿動作，但實質差很遠，有機會一起滑時幫你在黑缐拍一段你再比較一下。
你再滑多些便知沒你想那麼簡單，滑雪時當有速度時，你身體的協調性便會大大降低，就算是在綠缐冰面時，也很難控制。norman 寫:不，你弄錯一件事，這個動作我並未模仿誰的，這是我為了加強要練一個伸縮動作的彈性及一個很特別的動作而去想出這個方法練的。
而這J.F的影片是我在去年野澤滑完雪回來後才看到他的影片，然後從中截這一個彎出來的。
我認為差不遠了，我剛順便再把我練這動作第一次拍的影片貼給你們看，這是失敗的影片，因為收縮的不夠低，沒有達到我的要求，收縮不夠低是無法形成我要練的一個特別動作的。
而我一直貼給你們看的是我第三次拍的，那時已經下午四點了，沒時間拍了，所以是最後一趟，算是勉強還稍入得眼一點而已，但拿來講已足夠了。
你看我這第一次拍的，收縮不夠，像不像這兩天貼的影片動作？
http://youtu.be/jlVHb4p68so
http://youtu.be/w2Sh2_r3Szk
你滑得出他那樣時，可不可以收我做徒弟norman 寫:這動作練完後，滑起來的動作應該是像這個樣子的，但因為我才只練半天而已，又沒有個人的雪鞋及雪板，所以我只能這麼推測而已，但應該是八九不離十的。
http://youtu.be/BASTz0J3W4M
你很難想像我為何會有這信心，這是有原因根據的，如果下次出門滑雪，先不碰饅頭，我先花幾天的時間就專門特別練這個動作，從綠線一路練到黑線，因為又是兩年沒滑雪，我需要三天的時間適應黑線的陡度，還得先去買一副個人的滑雪裝備，這樣我們只要一起滑五天，你應該就能看到我在黑線上做出我要做的動作了。pku 寫:
你再滑多些便知沒你想那麼簡單，滑雪時當有速度時，你身體的協調性便會大大降低，就算是在綠缐冰面時，也很難控制。
我也有經常在家滑雪，但我跟你不同的地方是我在滑幾日便可在雪場實習，想的跟滑出來經常是兩回事，而你是在家滑一，兩年，才有機會到雪場實習。我現在講你是不會相信，到有機會一齊一起滑便知結果。
沒那麼誇張吧？pku 寫:你滑得出他那樣時，可不可以收我做徒弟
在大部分地形，雪質，都能滑得快速，暢順，身隨意轉，便是滑雪高手的境界。用什麼方法滑，我覺得不重要，norman 寫:沒那麼誇張吧？
不過下次出門滑雪只專練這個動作，應該是有機會逹到的，就算沒全像，八成應該是沒問題，最近老是講這個，害我腳又癢了，只好努力看看今年冬天能不能出門滑雪了。
PS. 我忘了提一件事，這是收縮釋壓的滑法喔，比伸展釋壓更難。
叫師父太沈重，因為就得負責仔細教會。pku 寫:在大部分地形，雪質，都能滑得快速，暢順，身隨意轉，便是滑雪高手的境界。用什麼方法滑，我覺得不重要，
如你能滑得這個境界，我叫你一聲師父是我的榮幸
學無前後，達者為先，我不會像偽太極，整天什麼幾十年滑雪經驗，掛在咀邊
滑雪時有兩種縮腿動作，一種是順應地形，被雪包頂上去的被動縮腿。norman 寫:「拉提收縮」就是這樣的一個動作，你想想看，我都能隨時隨地能做像這樣懸空就能收縮的動作，我還會在乎地形跟動作變化嗎？我唯一在乎的就只有地心引力而已，我只要想辦法維持相同的壓力把動作跟刻線做出來就行了，所以接下來我就把正確傾再加入進去，所以收縮的動作再加上自身旋轉的動作，這就是我說的把雙腳收縮到極限才會產生我要練的動作，收到極限後，如果身體沒有正確傾及自轉及自主收縮，就會被甩出去(摔出去)，這重心動作是變化非常快的。
就說下次真有機會一起滑不就知道了嗎？snowrider 寫:說弱慢兄對於吃很有研究
這個我同意!
但是若說到他懂滑雪?
我只能說他吹牛吹得累不累呀?!
Remember what you have said here, “stick with,” but you don't know what the “math and sci” methods are. You may have some “critical thinking” training, but your “critical thinking” lacks of “scientific” discipline.B2L2 寫:Math and sci doesn't lie, so let's stick with.
Asking question to pretend that you responding? 弱慢族的denials.So you have another definition, or something you don't understand that you need more explanation?
There is no such thing as “plainly wrong” in “math and sci” discipline, you either "prove" it or "disprove" it, if you cannot disprove it and insist on the wrong conclusions you are in denials, or other way of saying, you don't know what constitute a “proof,” and you don't know how to “prove” things.You quoted the very 1st formula and get it wrong. You basically lost the whole discussion already. The quoted formula describes the relation between R and V, but it didn't imply what you claimed is correct. You said "mathematically, the longer the turn radius the faster the speed" is plainly wrong, unless "centripetal acceleration is equal".
Assuming “all else equal” is the “standard practice” of scientific method/discipline, one more proof that you lack of “scientific” methods/discipline.I asked the question again, why and how you could assume the centripetal acceleration is equal in these two cases? Even Norman could name one thing that affects centripetal force, he named lean angle. How could you assume that the bigger turn and small turn both have the same lean angle from the skier?
“白痴邏輯”‧ No, you play soccer may make you legs thicker, but not “longer,” and a human body does not grow as 1+1=2, your premises are wrong, and your conclusion is also wrong. And noone here has assumed what you've assumed.Let's re-use your logic here.
A person height = length of lower body + length of upper body
With the person height the same, the longer his lower body, the shorter his upper body. Fair. Now I say playing soccer will make his legs longer. Putting the condition "will all else equal" (i.e. his height remains the same). Could then I conclude that playing soccer will shorten his upper body?
Is this logic make sense to anyone?
Apply this back to skiing, does it make any sense to assume the longer turn radius to have the same centripetal force as the shorter turn?
It may not mean anything to you, but all other “scientists” know what it means, and they have used it to sent man travels to the moon.In math, nobody don't care about approximate value of "a". If you want to draw a conclusion between the relation between R and V, you will have to use a constant "ac" value. Otherwise, your conclusion means nothing at all.
And your denial doesn't make you're right, and not "keep quite" doesn't mean you are asking questions, but whining.In math, nobody have to keep "quiet". There is only right or wrong. Even I keep quiet doesn't make your right.
Not sure what you're whining about here.You're the person using the "the higher the KE gives higher performance" statement. The question should be for yourself, and I even said to stick with this for discussion. What're you whining about?
The question here is not “kill ratio,” but “performance.”P-51 turns better, but Me262 has much better speed performance, and in air wars speed is the king, (and that's why in skiing downhill downhill is called the “king of the skiing,”) which is proven in Vietnam war.Did the P-51 ever shot down any ME262?
You lack of aeronautical knowledge, and your math is just as bad. See that little “m” there in the formula? That's a “variable” that you have not accounted for, not to mention that engine power and wing design all make major difference on airplane performance, so even they have the same KE, their performance will be likely different. The relationship of the KE and performance in skiing can be easily see on a black slope, without sufficient speed (higher KE) you cannot turn well on it.Back to math for a sec. If both ME262 and P-51 carry a weight of 10,000lb, both travelling at 400mph. Using "KE=1/2* m*V*V", they both have the same KE. Is there still performance difference between the two plane? If you simply use KE for measurement for performance, at this case they have the same. This is what I disagree on using KE for performance measure.
I think that you are confused about “spinning” with “travelling in a curved path,” wrong subject, and as it is not travelling, of course it has no “linear KE,” nevertheless, do you think whether or not that spinning object has a KE?i) "angular velocity" is not "linear". When an object spin at the same spot for 360degree/min, its linear velocity = 0, its angular velocity is 6 degree/sec. Please check your definition again.
[the object also have a 0 linear KE, it's angular KE is not, please check your definition as well.]
I think that you confused about “straight” with “linear” too, all “lines” are “linear,” so a curve line is “linear.”ii) Are we talking about the ski track? The ski track left behind is clearly in a curve. I can't agree that you name it a "linear" line.
Thanks for proving yourself are math/physics/science challenged.Again, in math, no one cares about "estimate". KE is defined by the formula you quoted. If you know m and V, no one needs to estimate. If you don't know the KE, you couldn't conclude which one has higher performance (since you said higher KE equals to higher performance). If you're guessing/estimating, then you're guessing/estimating.
If you could prove one thing math/sci/physically, then the prove shouldn't required people's experience in doing the two different turns. Your question is unrelated to this math prove. If this is your way to exit your ill-prove, then said it that way.
Yes, I did predict that you would deny it. What you throw out just bunch of “terminology” that you “copy&paste” from somewhere, and you have no ideas how they “relate,” and your analysis method is not scientific, and all that mumble jumble just to cover that you cannot answer my simple question, “what is “higher performance” in skiing?” Yup, “shameful critic, shameful person,” wanna try [to answer] it again?Wait until you could answer the questions and finish your proof before saying this. You have so many wrong and misleading info.
To prove you wrong, you could read: http://www.physlink.com/Education/AskExperts/ae154.cfmtaichiskiing 寫:There is no such thing as “plainly wrong” in “math and sci” discipline, you either "prove" it or "disprove" it, if you cannot disprove it and insist on the wrong conclusions you are in denials, or other way of saying, you don't know what constitute a “proof,” and you don't know how to “prove” things.
Centripetal acceleration is in this formula, how could you consider it is "else"?taichiskiing 寫:Assuming “all else equal” is the “standard practice” of scientific method/discipline, one more proof that you lack of “scientific” methods/discipline.
The same “白痴邏輯” applied to what you claimed.taichiskiing 寫:“白痴邏輯”‧ No, you play soccer may make you legs thicker, but not “longer,” and a human body does not grow as 1+1=2, your premises are wrong, and your conclusion is also wrong. And noone here has assumed what you've assumed
You're a pilot, right. Of course you should have better knowledge. I said they both carry the same weight (the sum of its own weight of the plane and extra items) . So "m" is the same for both cases.taichiskiing 寫:You lack of aeronautical knowledge, and your math is just as bad. See that little “m” there in the formula? That's a “variable” that you have not accounted for, not to mention that engine power and wing design all make major difference on airplane performance, so even they have the same KE, their performance will be likely different. The relationship of the KE and performance in skiing can be easily see on a black slope, without sufficient speed (higher KE) you cannot turn well on it.
Maybe you're the one getting confused.taichiskiing 寫:I think that you are confused about “spinning” with “travelling in a curved path,” wrong subject, and as it is not travelling, of course it has no “linear KE,” nevertheless, do you think whether or not that spinning object has a KE?
Again, you're the one getting confused. Go correct yourself by learning:taichiskiing 寫:I think that you confused about “straight” with “linear” too, all “lines” are “linear,” so a curve line is “linear.”
That's because more than half of you post are BS, helpless indeed.B2L2 寫:More than half of the message is unrelated verbal bashing. Helpless.
Don't bring in other people's works here when you cannot recite them with your own mouth, I'm not arguing with them, and they are not arguing with me, and you may not know what are they talking about. What you quote his saying has no argument related to my theory "the longer the turn radius the faster the speed". Your quote is incomplete and garble, do you know what is he talking about? I think that he is arguing on a subject that internal energy state doesn't affect the external orbit and velocity, which is correct, there's no argument. To test my theory is simple, just go out there to ski yourself (then that is real “all else are equal”), do some series“long” turns and “short” turns, see if you can tell the difference.Let continue the math and sci part since that what I'm only interested in.
To prove you wrong, you could read: http://www.physlink.com/Education/AskExperts/ae154.cfm
There are at least two examples there against your claimed theory of "the longer the turn radius the faster the speed".
Answered by: Yasar Safkan, Ph.D. M.I.T., Software Engineer, Istanbul, Turkey
"So, all in all, rotational motion itself does not put a constraint on how r and v are related. All it brings is one equation, which says the centripetal force is mv2/r. The second side of the equation is supplied by the nature of the force."
You could go argue over there if you want to said no.
Centripetal acceleration is in this formula, how could you consider it is "else"?
Yup, “the same “白痴邏輯”.”The same “白痴邏輯” applied to what you claimed.
I think that you are confused about “maneuvering [skills]” with “performance,”guess that's why you couldn't answer my question, “what is “higher performance” in skiing?”You don't know the answer.You're a pilot, right. Of course you should have better knowledge. I said they both carry the same weight (the sum of its own weight of the plane and extra items) . So "m" is the same for both cases.
And thanks for saying that "even they have the same KE, their performance will be likely different". This is why I said using KE as a performance measurement is not good. Any more question?
No, we are talking “circular motions” not “rotational energy,”so, you are the one who gets confused.Maybe you're the one getting confused.
http://en.wikipedia.org/wiki/Rotational_energy
Your narrow interpretation doesn't invalidate my theory, and there are more math and physics go into those terminology than your Wikipedia.Again, you're the one getting confused. Go correct yourself by learning:
http://en.wikipedia.org/wiki/Curvilinear_motion
http://en.wikipedia.org/wiki/Linear_motion
Quote: "Linear motion is a motion along a straight line"
http://www.columbia.edu/itc/sipa/math/nonlinear.html
Quote: "The graph of a non-linear function is a curved line. A curved line is a line whose direction constantly changes"
Have fun and enjoy learning in your old age.
It was you who claimed with all-else-equal, "the longer the turn radius the faster the speed". And people proved it wrong there.taichiskiing 寫:Don't bring in other people's works here when you cannot recite them with your own mouth, I'm not arguing with them, and they are not arguing with me, and you may not know what are they talking about. What you quote his saying has no argument related to my theory "the longer the turn radius the faster the speed". Your quote is incomplete and garble, do you know what is he talking about? I think that he is arguing on a subject that internal energy state doesn't affect the external orbit and velocity, which is correct, there's no argument. To test my theory is simple, just go out there to ski yourself (then that is real “all else are equal”), do some series“long” turns and “short” turns, see if you can tell the difference.
I'm not here to answer this question. I'm here to prove you wrong. But knowing what's my definition didn't make your theory right. We could make a new topic for that when I feel like it.taichiskiing 寫:I think that you are confused about “maneuvering [skills]” with “performance,”guess that's why you couldn't answer my question, “what is “higher performance” in skiing?”You don't know the answer.
You asked "whether or not that spinning object has a KE", you forgot? And that's my answer to your question. Rotational energy could also be called as angular kinetic energy.taichiskiing 寫:No, we are talking “circular motions” not “rotational energy,”so, you are the one who gets confused.
Have you figured out what is linear and what is non-linear yet? If you don't know and understand common teams, you don't have much room to prove yourself right.taichiskiing 寫:Your narrow interpretation doesn't invalidate my theory, and there are more math and physics go into those terminology than your Wikipedia.
You indeed a good example. Don't need to say thanks to yourself.taichiskiing 寫:Yup, I did learn a lot about lower end humanity here, thanks for the good examples.
