WEBVTT

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<b>上面写着KN 千牛顿</b>

00:00:04.863 --> 00:00:12.738
<b>看完这段视频 你会比其他99%的攀岩者有更好的理解</b>

00:00:12.988 --> 00:00:15.488
<b>KN 到底意味着什么意思</b>

00:00:16.071 --> 00:00:19.946
<b>以及攀爬冲坠过程中所涉及的力是哪些</b>

00:00:20.488 --> 00:00:27.155
<b>然后我会解释为什么大距离的坠落比小距离的坠落要柔和得多</b>

00:00:27.155 --> 00:00:30.155
<b>但首先 让我们看看力是什么</b>

00:00:30.155 --> 00:00:32.723
<b>我喜欢和我的Instagram粉丝一起互动</b>

00:00:32.723 --> 00:00:34.571
<b>所以我决定问问他们</b>

00:00:34.571 --> 00:00:38.780
<b>当他们听到“力”这个词时 他们会想到什么</b>

00:00:38.780 --> 00:00:42.571
<b>一半的人说这和《星球大战》 有关</b>

00:00:43.488 --> 00:00:44.321
<b>很好</b>

00:00:44.655 --> 00:00:50.530
<b>在你觉得我Instagram上一半的粉丝都很聪明之前</b>

00:00:50.655 --> 00:00:53.780
<b>我不得不说 大多数人根本没有投票</b>

00:00:53.895 --> 00:00:55.561
<b>所以我想象大家可能是这个状态</b>

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<b>力指的是什么</b>

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<b>好的 那些聪明的人说 </b>

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*<i>力 是 质量</i> 加速度 **

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<b> 这是牛顿第二运动定律</b>

00:01:09.280 --> 00:01:11.446
<b>这个人提出了这个定律 </b>

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<b>这就是为什么我们用牛顿这个单位来测量力</b>

00:01:14.446 --> 00:01:17.113
<b>当你思考它的时候 </b>

00:01:17.238 --> 00:01:18.905
<b>想象一下牛顿</b>

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<b>所以我们用kg 作为质量单位</b>

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<b>加速度 以m/s²为单位</b>

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<b>力以n（牛顿）来做单位</b>

00:01:42.988 --> 00:01:48.071
<b>为了更好地理解这个公式 它就像1牛顿 </b>

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<b>推动一千克的质量</b>

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<b>使质量的加速度是1m/s²</b>

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<b>这里有一个锁扣</b>

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<b>如果我把全身重量都压在上面 </b>

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<b>像这样</b>

00:02:06.488 --> 00:02:10.155
<b>问题是 现在这个锁扣的力是多少</b>

00:02:10.155 --> 00:02:12.363
<b>如果我们回头看这个公式 </b>

00:02:12.613 --> 00:02:15.613
<b>我们可以说 m 就是我的质量</b>

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<b>乘以加速度 </b>

00:02:19.780 --> 00:02:23.905
<b>加速度是多少 我挂在树上 没有运动 没有加速度</b>

00:02:25.113 --> 00:02:27.238
<b>或者有一个加速度</b>

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<b>你们可能见过这个实验 </b>

00:02:33.780 --> 00:02:36.780
<b>有一个轻的物体和一个重的物体</b>

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<b>问题是 如果我同时放开它们 </b>

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<b>哪个会先着地</b>

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<b>让我们试一试</b>

00:02:55.946 --> 00:02:58.571
<b>所以是的 它们同时下落到地面 </b>

00:02:58.696 --> 00:03:01.946
<b>因为重力就是这样 它让物体下落</b>

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<b>以同样的加速度 9.8m/s²</b>

00:03:15.905 --> 00:03:18.030
<b>所以当我挂在锁链上的时候</b>

00:03:18.613 --> 00:03:20.113
<b>地心引力把我往下拉</b>

00:03:20.488 --> 00:03:23.196
<b>但是为了让我不向下移动 </b>

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<b>一定有一个相反的力 </b>

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<b>把我拉上来 </b>

00:03:27.488 --> 00:03:28.905
<b>这里我有一个弹簧</b>

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<b>当重力将岩石向下拉时 </b>

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<b>弹簧将岩石向上拉</b>

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<b>这个锁扣实际上就像一个非常非常硬的弹簧</b>

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<b>它把我拉上来</b>

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<b>当我挂在锁扣上时 </b>

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<b>锁扣的分子会趋于分散</b>

00:03:46.196 --> 00:03:49.946
<b>原本分子聚集的力量会产生类似拉的作用 </b>

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<b>这种在低拉力下的扩张你是看不到的</b>

00:03:54.280 --> 00:03:55.821
<b>但是大的力就可以</b>

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<b>结果是这个锁扣举起了我的体重</b>

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<b>以同样的9.8m/s²的加速度 </b>

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<b>也就是大约600N</b>

00:04:16.321 --> 00:04:18.655
<b>是啊 六百个这样的东西</b>

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<b>才能拉住我这样的瘦子 </b>

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<b>好了 我们继续</b>

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<b>这个主锁显示它能承受26kn的重量</b>

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<b>KN等于一千牛顿</b>

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<b>所以这意味着它能承载40个我</b>

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<b>我希望我有一台克隆机器</b>

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<b>这样我就可以向你们展示这个</b>

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<b>然后想象一下我能制作多少视频</b>

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<b>如果你想见我们</b>

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<b>创建更多像这样的视频 </b>

00:05:05.905 --> 00:05:08.905
<b>点击点赞和关注按钮 它确实有帮助</b>

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<b>我保证 </b>

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<b>我会把从你们那里得到的每一分钱都花在买克隆机器上</b>

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<b>好吧 你可以用一个锁扣挂40个我</b>

00:05:24.905 --> 00:05:26.030
<b>这很厉害</b>

00:05:26.821 --> 00:05:29.530
<b>虽然有些事情你必须知道 </b>

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<b>首先 这些负荷参数是针对新装备的</b>

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<b>磨损不包括在这个评级之内</b>

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<b>这有多糟糕</b>

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<b>我问了我在油管HowNOTtoHighline频道的朋友Ryan</b>

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<b>因为他有破坏东西的爱好</b>

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<b>根据他的测试</b>

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<b>大多数金属都很耐用</b>

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<b>而软性材料的东西</b>

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<b>完全不同</b>

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<b>[Ryan] BD的 22KN 扁带</b>

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<b>什么</b>

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<b>MBS是多少 22kn吗</b>

00:06:13.321 --> 00:06:17.321
<b>是的 一个性能为22kn的扁带</b>

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<b>在6kn左右就断了</b>

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<b>接下来是另一个例子</b>

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<b>[Ryan] 这是另一个状态很好的扁带</b>

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<b> 没拉扯过</b>

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<b>[Ryan] 对 没拉扯过</b>

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<b>我会把我的狗拴在上面</b>

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<b>我可不会把一条大狗拴在上面 </b>

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<b>让我们看看你能用这个牵住多大的狗</b>

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<b>哦 一个吉娃娃吗?</b>

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<b>是的 所以如果你是那种喜欢省钱的人 </b>

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<b>用着很旧的且磨损的扁带</b>

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<b>祝你好运</b>

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<b>24kn</b>

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<b>这并没有延伸太多 </b>

00:07:05.655 --> 00:07:08.655
<b> 哦 猜猜猜</b>

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<b>你猜怎么着?</b>

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<b>[Ryan] 4kn</b>

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<b>搞什么鬼 伙计 </b>

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<b>4kn 那这个扁带能承受多少</b>

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<b>这很简单 只要用4000除以9.8</b>

00:07:24.488 --> 00:07:26.863
<b>如果你想简单一点 除10代替 </b>

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<b>你得到400公斤 </b>

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<b>这听起来很多</b>

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<b>好吧</b>

00:07:35.946 --> 00:07:40.696
<b>所有这些都是我一直在讲的从力到千克的换算</b>

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<b>都是基于重量是静止的这个事实 </b>

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<b>一旦物体开始下落 一切都会改变</b>

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<b>你们刚才看到的是DMM的一段视频 </b>

00:07:56.780 --> 00:07:59.780
<b>他们扔下了80公斤的重物</b>

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<b>破坏了一个全新的Dyneema扁带</b>

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<b>我的目的不是吓唬你 </b>

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<b>恰恰相反 </b>

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<b>我想让大家意识到 攀岩装备并不是魔法</b>

00:08:10.988 --> 00:08:14.238
<b>如果你使用错误 它可能会失效</b>

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<b>事实上 </b>

00:08:17.905 --> 00:08:19.696
<b>你知道岩友在攀爬失败时</b>

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<b>喜欢说的这个笑话吗?</b>

00:08:21.905 --> 00:08:24.196
<b>今天的引力有点大</b>

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<b>事实证明这是真的</b>

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<b> 重力确实每个月都在变化</b>

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<b>所以</b>

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<b>如果你是那种喜欢抱怨今天湿度</b>

00:08:35.905 --> 00:08:37.196
<b>或温度不好的人</b>

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<b>现在你有权利抱怨今天是糟糕的重力日</b>

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<b>好了 让我们看看当物体开始下落时会发生什么 </b>

00:08:51.113 --> 00:08:53.321
<b>这是一个10米长度的下落</b>

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<b>让我们看看这样的下落会给攀登者带来多大的力</b>

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<b>它的公式和之前的差不多 </b>

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<b>除了需要乘以这个</b>

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<b>攀爬者下落的距离</b>

00:09:07.071 --> 00:09:11.030
<b>然后除以攀爬者减速的距离</b>

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<b>你有没有注意到 </b>

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<b>攀爬者落下时的冲击力相对比较软</b>

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<b>所以想象一下在高速公路上开车 </b>

00:09:26.613 --> 00:09:31.030
<b>通过轻轻地踩下刹车去停车</b>

00:09:31.571 --> 00:09:32.655
<b>没有问题对吧</b>

00:09:33.030 --> 00:09:35.280
<b>现在想象你没有开那么快</b>

00:09:35.280 --> 00:09:37.655
<b>你在一个城市里 你开得很慢 </b>

00:09:37.655 --> 00:09:39.196
<b>但是你撞上了一座桥</b>

00:09:40.280 --> 00:09:43.363
<b>感觉不太好 对吧?</b>

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<b>这是我想让你们记住的第一件事</b>

00:09:47.238 --> 00:09:49.905
<b>对攀登者的冲击</b>

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<b>永远是攀登者下落的距离除以下落面距离</b>

00:09:57.530 --> 00:09:59.196
<b>让我们计算一下</b>

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<b>下落的距离大约是4个快挂 </b>

00:10:02.405 --> 00:10:05.905
<b>而下降的距离大约是2个半快挂</b>

00:10:06.571 --> 00:10:09.571
<b>我们得到大约860牛顿</b>

00:10:09.571 --> 00:10:13.821
<b>或者如果我们用这个标准的80公斤的攀爬者来代替</b>

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<b>大约是1.3kn</b>

00:10:18.571 --> 00:10:19.488
<b>这并不多</b>

00:10:20.155 --> 00:10:22.530
<b>尽管这个公式有一个小问题 </b>

00:10:22.530 --> 00:10:28.446
<b>因为它总是会给你一个值 比实际值略低</b>

00:10:28.905 --> 00:10:31.821
<b>但是展示更精确地计算 </b>

00:10:31.821 --> 00:10:35.738
<b>这意味着你们中的大多数人可能会离开这个视频</b>

00:10:36.071 --> 00:10:37.905
<b>但我们不需要这样做</b>

00:10:37.905 --> 00:10:41.613
<b>因为我们可以依靠现实生活中的实验数据</b>

00:10:41.863 --> 00:10:45.030
<b>谁为我们提供这些数据</b>

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<b>大家好 我是Ryan Jenks </b>

00:10:46.738 --> 00:10:49.071
<b>广告已经足够了</b>

00:10:49.363 --> 00:10:50.780
<b>在这个视频中 </b>

00:10:50.780 --> 00:10:54.196
<b>他们放了一个设备来测量攀爬者所受的力</b>

00:10:54.196 --> 00:10:56.488
<b>然后做了一系列的冲坠</b>

00:11:07.280 --> 00:11:09.113
<b>为了科学</b>

00:11:13.988 --> 00:11:15.821
<b>1.87kn的力</b>

00:11:16.113 --> 00:11:17.238
<b>所以在我看来</b>

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<b>大部分的冲坠都是一个很好的保护案例</b>

00:11:20.488 --> 00:11:22.571
<b>低于2kn</b>

00:11:22.571 --> 00:11:26.071
<b>现在我们来看看这两个极端的例子</b>

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<b>左边的攀登者在挂片上方5米 </b>

00:11:29.571 --> 00:11:31.863
<b>所以会有10米长的冲坠</b>

00:11:31.988 --> 00:11:34.113
<b>加上绳索的延展性</b>

00:11:34.113 --> 00:11:37.071
<b>保护者可能有一米的余量</b>

00:11:37.071 --> 00:11:41.405
<b>然后在快挂之间可能还有一米的余量</b>

00:11:41.696 --> 00:11:44.655
<b>所以总的来说 我们将看到12米的坠落</b>

00:11:44.988 --> 00:11:48.280
<b>而右边的攀爬距离挂片只有一米</b>

00:11:48.613 --> 00:11:51.405
<b>假设保护员非常害怕</b>

00:11:51.405 --> 00:11:54.530
<b>他要硬生生地接住攀爬者 并没什么缓冲</b>

00:11:54.780 --> 00:11:56.821
<b>我们看到的是两米高的坠落</b>

00:11:58.155 --> 00:12:01.030
<b>所以从12米高的地方摔下来 </b>

00:12:01.030 --> 00:12:02.946
<b>还是从2米高的地方摔下来 </b>

00:12:03.155 --> 00:12:06.238
<b>你觉得哪个对攀岩者来说比较软</b>

00:12:06.488 --> 00:12:09.905
<b>让我们看一下 我们已经知道了会掉下来多少</b>

00:12:09.905 --> 00:12:14.530
<b> 但现在我们需要找出两种情况下的减速距离</b>

00:12:14.988 --> 00:12:17.280
<b>这主要取决于两个因素</b>

00:12:17.571 --> 00:12:20.363
<b>首先是保护者的位移</b>

00:12:20.738 --> 00:12:22.071
<b>一个非常非常大的冲坠 </b>

00:12:22.071 --> 00:12:25.071
<b>保护员大概会飞两米左右</b>

00:12:26.280 --> 00:12:27.280
<b>在小的冲坠时 </b>

00:12:27.280 --> 00:12:30.280
<b> 让我们假设 对于初学者来说有非常常见的错误</b>

00:12:30.280 --> 00:12:34.030
<b>保护员只是收紧绳子和反应迟钝</b>

00:12:34.488 --> 00:12:37.738
<b>第二个因素是绳子的伸展性</b>

00:12:38.238 --> 00:12:40.155
<b>绳子制造商声称 </b>

00:12:40.155 --> 00:12:43.488
<b>如果你把80公斤的质量放在一根动力绳子上</b>

00:12:43.821 --> 00:12:46.613
<b>像这样静止不动</b>

00:12:47.030 --> 00:12:49.280
<b>绳子会伸长10%</b>

00:12:49.280 --> 00:12:52.280
<b>当你先锋状态下冲坠 动态拉伸将会 </b>

00:12:52.530 --> 00:12:54.696
<b>高达30%</b>

00:12:55.488 --> 00:12:58.655
<b>嗯 高达30%对我们来说不是很有帮助</b>

00:12:58.655 --> 00:13:01.780
<b>我们需要知道的是绳子</b>

00:13:02.363 --> 00:13:06.321
<b>从2到4千牛顿的拉力时的变化</b>

00:13:06.863 --> 00:13:09.280
<b>再一次 我给Ryan发了消息</b>

00:13:09.280 --> 00:13:12.988
<b>所以我要拉一根动态绳子 看看它拉伸了多少</b>

00:13:12.988 --> 00:13:14.863
<b>一开始 我们以为会很简单</b>

00:13:14.863 --> 00:13:16.113
<b>去公园就行</b>

00:13:16.113 --> 00:13:18.321
<b>用不同的力拉伸绳子</b>

00:13:18.405 --> 00:13:20.613
<b> 测量绳子的伸长</b>

00:13:21.155 --> 00:13:24.821
<b>好吧 有时候简单是困难的</b>

00:13:25.155 --> 00:13:28.738
<b> 然后你把绳子拉到一定的力 然后把它留在那里</b>

00:13:29.071 --> 00:13:31.280
<b>力开始落在绳子上</b>

00:13:31.571 --> 00:13:33.113
<b>绳子就这么断了</b>

00:13:33.571 --> 00:13:36.863
<b>虽然这很有趣 但对我们来说并不致命</b>

00:13:36.863 --> 00:13:39.321
<b>他需要做的唯一一件事</b>

00:13:39.321 --> 00:13:42.321
<b>就是以他所希望的力尽可能快地拉绳子</b>

00:13:42.488 --> 00:13:44.488
<b>然后测量拉伸程度</b>

00:13:46.113 --> 00:13:48.071
<b>天啊 那是七米标志</b>

00:13:49.738 --> 00:13:52.196
<b>6.9米 </b>

00:13:53.155 --> 00:13:59.530
<b>这是4kn情况下动力绳的伸展长度</b>

00:13:59.530 --> 00:14:01.571
<b>但还有另一个有趣的因素 </b>

00:14:01.571 --> 00:14:04.196
<b>一旦你给绳子施加大的力</b>

00:14:04.446 --> 00:14:08.363
<b>绳子需要一段时间才能恢复到原来的长度 </b>

00:14:08.613 --> 00:14:11.113
<b>这就是所谓的绳索休息</b>

00:14:11.571 --> 00:14:13.863
<b>看这些变化真的很酷</b>

00:14:13.863 --> 00:14:17.030
<b>看到龟龟慢慢被拉回来了吗?</b>

00:14:19.780 --> 00:14:21.113
<b>超级有趣</b>

00:14:22.238 --> 00:14:24.780
<b>也许我现在比你更感兴趣</b>

00:14:25.363 --> 00:14:28.863
<b>他在公园里拉了四个小时的绳子</b>

00:14:29.238 --> 00:14:33.738
<b>结果是在2到4kn的力作用下</b>

00:14:33.946 --> 00:14:37.363
<b>绳子拉伸到大约20%</b>

00:14:37.905 --> 00:14:40.821
<b>很好 我们把它用到计算中</b>

00:14:41.155 --> 00:14:45.238
<b>在一个大的下落过程中 我们总共有27米的绳子 </b>

00:14:45.238 --> 00:14:49.280
<b>所以这将是5.4米的拉伸</b>

00:14:49.696 --> 00:14:52.738
<b>在一个小的下落过程中 我们有5米长的绳子 </b>

00:14:52.738 --> 00:14:54.988
<b>那就是1米的拉伸</b>

00:14:55.196 --> 00:14:58.363
<b>然而 我们的保护员却惊慌失措 奋力挣扎</b>

00:14:58.738 --> 00:15:05.613
<b>所以他会自己留半米 给攀登者留下半米</b>

00:15:06.655 --> 00:15:09.821
<b>对于攀岩者来说 长距离的冲坠 </b>

00:15:09.821 --> 00:15:15.280
<b>比小的冲坠要软2.5倍</b>

00:15:16.446 --> 00:15:19.071
<b>我喜欢有趣的事实 这是另一个 </b>

00:15:19.183 --> 00:15:21.350
<b>想象一下你没有完攀</b>

00:15:21.846 --> 00:15:27.388
<b>但是那天的湿度 温度 甚至重力都很好</b>

00:15:28.446 --> 00:15:30.613
<b>你仍然可以责怪月亮</b>

00:15:30.613 --> 00:15:32.571
<b>[旁白]可以忽略不计 但确实</b>

00:15:33.223 --> 00:15:38.556
<b>当月亮正对着你时 你的体重会减少一百万分之一</b>

00:15:38.821 --> 00:15:42.863
<b>所以 如果你想在月亮正对着你的时候完成线路</b>

00:15:43.530 --> 00:15:45.155
<b>那加油</b>

00:15:45.571 --> 00:15:50.071
<b>我记得当时我在攀爬一条35米长的路线</b>

00:15:50.321 --> 00:15:53.113
<b>这是我第一次成功地把所有的动作连接起来</b>

00:15:53.280 --> 00:15:54.821
<b>到达顶部锚点时</b>

00:15:55.030 --> 00:15:58.696
<b>当我把绳子拉上来准备放入绳子的时候</b>

00:15:58.696 --> 00:16:01.280
<b>我的保护员看不清楚我</b>

00:16:01.280 --> 00:16:03.238
<b>所以他就给了我很大的绳子余量</b>

00:16:03.265 --> 00:16:09.431
<b>最重要的是 倒数那把挂片在很下面的位置</b>

00:16:10.201 --> 00:16:15.160
<b>所以当我把绳子往上拉的时候 我失去了平衡 摔了下去</b>

00:16:15.821 --> 00:16:18.905
<b>墙在我面前飞舞 </b>

00:16:18.905 --> 00:16:21.905
<b>我在想为什么我还在下落 嗯 这很不寻常</b>

00:16:21.946 --> 00:16:23.780
<b>然后我停下来 抬头看了看</b>

00:16:23.780 --> 00:16:26.155
<b>我上方大概有五六把快挂 </b>

00:16:26.155 --> 00:16:29.071
<b>大概有十五米的坠落</b>

00:16:29.535 --> 00:16:32.535
<b>但是下落的过程非常柔软 </b>

00:16:32.575 --> 00:16:34.158
<b>就像坐电梯一样 </b>

00:16:34.366 --> 00:16:36.575
<b>这是这个视频的另一个要点 </b>

00:16:36.848 --> 00:16:38.932
<b>如果攀爬者在很高的位置</b>

00:16:39.170 --> 00:16:41.586
<b>他有很多绳子来承受坠落 </b>

00:16:41.696 --> 00:16:44.696
<b>只要他不掉到什么东西上</b>

00:16:44.940 --> 00:16:48.440
<b>无论你如何保护 摔下去的时候会很轻</b>

00:16:49.221 --> 00:16:51.821
<b>然而 如果高度不那么高</b>

00:16:52.030 --> 00:16:54.780
<b>他没有那么多的绳子来吸收下落</b>

00:16:54.780 --> 00:16:58.988
<b>那么一个好的动态缓冲保护是非常重要的</b>

00:16:59.696 --> 00:17:02.530
<b>你可以问任何一个轻度攀岩者</b>

00:17:02.571 --> 00:17:07.363
<b> 有多少次他们的脚踝因为硬着陆而受伤</b>

00:17:07.655 --> 00:17:09.530
<b>好了 让我们换个话题</b>

00:17:09.530 --> 00:17:11.363
<b>我们来谈谈摩擦</b>

00:17:11.696 --> 00:17:17.030
<b>因为摩擦力越大 对攀登者来说 摔得越重</b>

00:17:17.363 --> 00:17:19.696
<b>这有一个非常极端的例子</b>

00:17:19.696 --> 00:17:22.696
<b>你们可以看到这里快挂成Z字形</b>

00:17:23.780 --> 00:17:27.655
<b>所以当我下落时 会有很大的摩擦力</b>

00:17:27.905 --> 00:17:29.071
<b>哇 为了科学</b>

00:17:34.280 --> 00:17:39.488
<b>所以摩擦力很大 靠近攀登者的绳子正常伸展</b>

00:17:39.738 --> 00:17:42.113
<b>但是保护者附近的绳子 </b>

00:17:42.321 --> 00:17:44.030
<b>不会拉伸太多</b>

00:17:44.321 --> 00:17:47.488
<b>这就像有是更短的绳子 同时有更重的保护员</b>

00:17:47.863 --> 00:17:52.405
<b>让护具承受的力只有2.5kn</b>

00:17:52.405 --> 00:17:55.405
<b>许多力像钟摆一样撞在墙上</b>

00:17:57.280 --> 00:17:59.363
<b>我们就是这样扭断脚踝的</b>

00:17:59.696 --> 00:18:03.071
<b>所以合理的增多快挂</b>

00:18:03.071 --> 00:18:05.446
<b>不仅可以帮助你进快挂和避免这种情况</b>

00:18:16.655 --> 00:18:20.363
<b>同时也减少了攀爬者承受的冲击力</b>

00:18:20.640 --> 00:18:25.306
<b>好 我们回到DMM弄断扁带的测试 </b>

00:18:25.613 --> 00:18:29.571
<b>Dyneema扁带是静态的 根本不会拉伸</b>

00:18:29.571 --> 00:18:32.988
<b>我希望你们现在已经明白这种突然的停止</b>

00:18:32.988 --> 00:18:34.863
<b>可以产生巨大的力</b>

00:18:34.988 --> 00:18:37.780
<b>如果没有明白 请别人扇你一巴掌</b>

00:18:37.780 --> 00:18:41.946
<b>你需要理解的基本就是在脸上的这个停顿</b>

00:18:42.030 --> 00:18:43.863
<b>所以让我们做一个非常大胆的</b>

00:18:43.863 --> 00:18:46.155
<b> 可能是一个非常不准确的猜测 </b>

00:18:46.155 --> 00:18:50.405
<b>这个扁带会大约延伸到5厘米</b>

00:18:51.280 --> 00:18:54.321
<b>所以如果我们放下80千克的质量</b>

00:18:54.506 --> 00:18:57.381
<b>扁带长度120厘米</b>

00:18:57.907 --> 00:19:01.615
<b>吸收距离只有5厘米 </b>

00:19:01.821 --> 00:19:05.196
<b>我们看到的是19kn</b>

00:19:06.196 --> 00:19:11.321
<b>如果这都不能把扁带弄断 那肯定会把你弄断</b>

00:19:12.821 --> 00:19:14.321
<b>如果你还在看 </b>

00:19:14.321 --> 00:19:18.071
<b>这可能意味着你至少应该有点书呆子气 </b>

00:19:18.488 --> 00:19:20.405
<b>这是给你的甜点</b>

00:19:21.363 --> 00:19:26.905
<b>没有引力 物体不会相互吸引</b>

00:19:27.071 --> 00:19:29.030
<b>只有空间和时间</b>

00:19:29.030 --> 00:19:31.155
<b>你觉得自己好像被推入了地下</b>

00:19:31.946 --> 00:19:33.988
<b>不是因为重力 </b>

00:19:34.238 --> 00:19:38.780
<b>而是因为你脑袋上时间比你脚上的时间变化得更快</b>

00:19:38.978 --> 00:19:41.533
<b>所以如果你想看到更多类似的内容 </b>

00:19:41.585 --> 00:19:44.710
<b>不要忘记订阅并支持我们的频道</b>