This is dye again,

I find this, see if it helps

http://www.newton.dep.anl.gov/askasci/gen01/gen01405.htm

dye

Sorry, I do not believe what the web site is saying.

Here is an experiment Sherman can do and help us understand the question:

Place the candle further and further away from the hair blower and see the effect.  (Test the air pressure.  The further the wind source, the smaller the low pressure.)

Use this distance, change the temerature of the wind blowing, perhaps by using the fridge and heating element of the dair dryer.  (Test for temperature.  Is it true that people in Arctic has an easier time blowing out candle than say, African?)

Lastly, to proof what the web site is correct, it should be impossible to blow out a lighter because you can't "blow off" the flame.  So change the fire source and try it again to see if there is any difference!

抽刀斷水

根據http://www.tutorvista.com/conten ... sion/combustion.php，燃燒的conditions如下：
1. 物質本身可燃
2. 氧氣
3. 溫度

那吹氣令其熄滅，究竟是令溫度下降是主因，抑或令氧氣的密度降低（降低氣壓）呢？

我猜用風筒吹，經過風筒發熱線後，部分氧氣就會燃燒走，所以沙文的實驗方法是有問題的。

最好是：

用一個氧氣筒，將氧氣加熱後向火柴或蠟燭噴出，咁就perfect喇！（不過實驗危險性高，建議沙文先立遺囑，到自己活得不耐煩時才進行）

dye

Are you sure the electric heating element of the hair dryer will "burn" any oxygen away?  How about a safer way with air from freezer, or air from top of a block of ice?  If temperature is an issue, cooler air should be able to do it better, right?

Actually I found an even more likely answer, it fits with all observations I seen so far in my life:

I think the wind blow the chain reaction of the fire away.  In order for the flame to continue, the last reaction must be in proximity with the next reaction in order to transfer the heat.  

With the air moving so fast, it outpace the reaction front.

This is observable as the wind gets stronger and stronger, the flame moves away from the head.  At certain wind speed, the flame will bound to be too far from the fuel source.

**  I think the temperature idea is correct only concerning candle because of the way the fuel is supplied (vapourization of the wax).  It is incorrect in the general sense.

沙文

回復 424# dye
Thx dye, your explaination seems make more sense 2 me.
但為了慎重起見, 我仍會在滿月宴上進行該項實驗

沙文

影相發燒友參加攝影比賽，題目係「大自然」
我的拍友影這張相參賽：


我不想重複他的作品，於是我這張相參賽:



但係連參加都參加唔到。報名處的小姐話我離題

點解雀仔築巢就自然，人起間屋就唔自然呢？

抽刀斷水

根據定義，自然和人為是對立的，人為的就是非自然。

因此，你叫人去幫你剪頭髮，斷唔會被稱為自然脫髮既。

沙文

回復 427# 抽刀斷水

烏龜先生同太太咁玩，係自然

難道我又玩同一個遊戲就是人為？

抽刀斷水

都幾人為架，至少烏龜伉儷唔駛除衫，沙文伉儷就要除衫。

沙文

回復 429# 抽刀斷水

咁女人生仔又夠要除褲，邊鬼度有「自然分娩」？

抽刀斷水

自然分娩係指仿效自然界既分娩方式咁解既。

沙文

回復 431# 抽刀斷水

咁我除衫先玩都係仿效自然界既遊樂方式啫

抽刀斷水

回復 432# 沙文


    都勉強可以咁講既，但如果遊樂之前係唔需要除衫，即係你平時都無著衫，咁就真正自然喇。

Just try it.

沙文

回復 433# 抽刀斷水

超您同老闆食食下飯忽然急屎，講聲 got a call from mother nature, 您咪又係要除褲先。您平時又用唐英年嘅辦法出街吖笨

沙文

咁死於自然呢？
譬如您行出街被基督徒行刺，咁就死於人為

但若是您馬上風死咗，咁係死於自然啦卦？

抽刀斷水

回復 434# 沙文


    「同老闆吃飯」根本就唔係自然既前題啦。自然應該係森林同其他動動一齊食，咁又更加唔駛除褲痾屎（因為無著）。

抽刀斷水

回復 435# 沙文


    死於自然 = 不是死於人為

因為個死法無人賴到，咪夾硬賴自然囉。

沙文

回復 437# 抽刀斷水


    "死於自然 = 不是死於人為"

即是，人都可以自然地、不是人為地死啦！咁就有得講嘞！點解您自然地死就得，自然地起間屋住就唔得？
請問，人做一樣嘢係咪自然，係用咩黎做標準？

抽刀斷水

回復 438# 沙文


    死於自然果個人都唔係自己想死丫嘛，自行了斷果D好似唔叫死於自然。

你起樓時係你想起而又起左，咁就唔得自然；但如果唔想起咁起樓，咁咪即係坐係度等佢自然風化、地震地殼移動之類咁起出黎囉，你咁起樓法就起得自然喇。

沙文

回復 439# 抽刀斷水


    咁咁咁咁咁咁咁咁咁咁  自然脫髮係自然啦卦？您自己講咖？我諗您都較大量地開始咗啦？