滑雪之道,簡單的說,不過是以高度換速度,以速度換高度;那正是滑翔機的飛法,所以滑雪與飛行一定有相同的操作的環境。有的,那就是沒有摩擦力或是小摩擦力的環境,所以它們在技術上的物理是一樣的,飛行的知識滑雪可以借用。我們先看看飛機/翅膀是怎麼飛的。前面說過,飛機之所以能飛是因為翅膀產生的浮力/lift。而翅膀能產生浮力是因為相對風/relative wind經過翅膀時分成兩部,一部份走翅膀上面,一部份走翅膀下面,因為翅膀側面的形狀/cord,走翅膀下面的空氣產生一個壓力大於翅膀上部空氣的壓力,所以把翅膀向上推,那是翅膀浮力的來源。相對風與翅膀所產生的角度叫Angle of Attack,在一個要緊的角度/critical angle以內,Angle of Attack的角度增加,浮力也增加,但是Angle of Attack增加到那要緊的角度/critical angle,翅膀的浮力消失,翅膀不在飛了,而飛機向下掉/falling out of sky,那叫“失速” 。不能飛失速的飛機,要還原/恢復飛行,減小Angle of Attack。那就是飛機翅膀的飛行。
When an airplane is flying, the G-force is applied to the whole airplane and everything in it. The following video clip demonstrated the impact of the G-force well. 1) look the water level in the water bottle during the turn, it remains level with the airplane, and 2) during the loop pull up, ~@2:07, see the guy screaming and his face, which is experiencing a 4G pull. G-force cannot be seen (what we see is only its trace after the fact), but it is soooo real.
Another interesting point here, curious about how you look when you get old? Look your face under 5G, that’s what gravity eventually will do to your face.
发表于 2018-11-5 11:34
When an airplane is flying, the G-force is applied to the whole airplane and everything in it ...
G-force cannot be seen (what we see is only its trace after the fact), but it is soooo real.
G-force
我想G-force裡面的G代表Gravity,但是,在他的相對論裡,愛因斯坦有更深的認識—G-force的產生是物體相對運動所產生的,叫“加速度”/acceleration—而我們的身体不能分辨這G-force/力量是地力呢還是加速度,反應都是一樣的。下面的影片shows an extreme case of how a G-force at work,