1 00:00:01,610 --> 00:00:03,943 - It says kilonewtons... 2 00:00:04,830 --> 00:00:06,700 And after this video, 3 00:00:06,700 --> 00:00:09,240 you will have a much better understanding 4 00:00:09,240 --> 00:00:12,940 than probably 99% of the rest of the climbers, 5 00:00:12,940 --> 00:00:16,010 what these kilonewtons actually mean, 6 00:00:16,010 --> 00:00:20,420 and what forces are involved in real climbing falls. 7 00:00:20,420 --> 00:00:23,710 And then I will explain why big, big whippers 8 00:00:23,710 --> 00:00:27,140 are often much softer than small falls. 9 00:00:27,140 --> 00:00:30,280 But first, let's find out what is force. 10 00:00:30,280 --> 00:00:32,610 I like to play with my Instagram followers, 11 00:00:32,610 --> 00:00:36,310 so I decided to ask them what comes to their mind 12 00:00:36,310 --> 00:00:38,710 when they hear the word force. 13 00:00:38,710 --> 00:00:40,040 Half of the people said 14 00:00:40,040 --> 00:00:43,440 that it has something to do with "Star Wars". 15 00:00:43,440 --> 00:00:44,590 Fair enough. 16 00:00:44,590 --> 00:00:46,480 And then before you start thinking 17 00:00:46,480 --> 00:00:50,640 that half of my Instagram followers are really smart, 18 00:00:50,640 --> 00:00:53,870 I have to say that majority of them didn't vote it at all. 19 00:00:53,870 --> 00:00:55,413 So I imagine something like... 20 00:00:55,413 --> 00:00:57,883 What is force? 21 00:00:57,883 --> 00:01:00,600 (lively music) (electronic buzzing) 22 00:01:00,600 --> 00:01:03,060 Okay, but those who wanted to sound smart 23 00:01:03,060 --> 00:01:07,150 said that force is mass times acceleration, 24 00:01:07,150 --> 00:01:09,860 which is the formula that Newton, this guy, 25 00:01:09,860 --> 00:01:10,917 came up with. 26 00:01:10,917 --> 00:01:11,820 - [Newton] Ooh yah. 27 00:01:11,820 --> 00:01:14,400 And that's why we measure force in Newtons. 28 00:01:14,400 --> 00:01:17,210 Which to me is a little bit funny when you think about it, 29 00:01:17,210 --> 00:01:18,550 imagine Newton. 30 00:01:18,550 --> 00:01:21,133 (gentle music) 31 00:01:22,230 --> 00:01:24,987 So we measure mass in kilograms, 32 00:01:27,555 --> 00:01:32,555 and we measure acceleration in meters per second squared. 33 00:01:35,480 --> 00:01:40,057 Then we should measure force in Newtons. 34 00:01:40,057 --> 00:01:42,965 (clapping) 35 00:01:42,965 --> 00:01:45,427 So to put this formula into perspective, 36 00:01:45,427 --> 00:01:48,990 it's like one Newton, this guy, 37 00:01:48,990 --> 00:01:52,250 is pushing one kilogram of mass 38 00:01:52,250 --> 00:01:55,330 and that makes that mass to accelerate 39 00:01:55,330 --> 00:01:58,870 by one meter per second, every second. 40 00:01:58,870 --> 00:02:01,560 So here I have a carabiner. 41 00:02:01,560 --> 00:02:06,470 If I put all my weight on it, like so, 42 00:02:06,470 --> 00:02:08,840 the question is, what's the force right now 43 00:02:08,840 --> 00:02:10,110 into this carabiner? 44 00:02:10,110 --> 00:02:12,470 So if we look back to the formula, 45 00:02:12,470 --> 00:02:15,920 we can say that mass is my mass 46 00:02:15,920 --> 00:02:18,543 multiplied by acceleration. 47 00:02:19,350 --> 00:02:21,300 What acceleration? I'm hanging on a tree. 48 00:02:21,300 --> 00:02:24,040 There is no movement, no acceleration... 49 00:02:24,945 --> 00:02:28,175 or is there an acceleration? 50 00:02:28,175 --> 00:02:29,882 (upbeat music) 51 00:02:29,882 --> 00:02:33,790 Look, so you've probably seen this experiment before, 52 00:02:33,790 --> 00:02:37,500 I have heavy object and a light object. 53 00:02:37,500 --> 00:02:39,410 And the question is, if I let go 54 00:02:39,410 --> 00:02:41,640 both of them at the same time, 55 00:02:41,640 --> 00:02:43,943 which one is gonna hit the ground first? 56 00:02:45,220 --> 00:02:46,053 Let's try. 57 00:02:55,910 --> 00:02:58,560 So yes, they fell at the same time, 58 00:02:58,560 --> 00:03:00,270 because that's what gravity does, 59 00:03:00,270 --> 00:03:04,370 it makes objects fall at exactly the same acceleration 60 00:03:04,370 --> 00:03:08,803 of 9.8 meters per second per second. 61 00:03:15,790 --> 00:03:18,510 So then I'm hanging on this carabiner, 62 00:03:18,510 --> 00:03:20,390 gravity is pulling me down. 63 00:03:20,390 --> 00:03:23,290 But in order for me to not move down, 64 00:03:23,290 --> 00:03:27,270 there must be opposite force, which would be pulling me up. 65 00:03:27,270 --> 00:03:29,490 Here I have a spring. 66 00:03:29,490 --> 00:03:32,670 While the gravity is pulling the rock down, 67 00:03:32,670 --> 00:03:35,370 the spring is pulling the rock up. 68 00:03:35,370 --> 00:03:39,230 So the carabiner is actually like a very, very stiff spring, 69 00:03:39,230 --> 00:03:41,150 which is pulling me up. 70 00:03:41,150 --> 00:03:44,270 The molecules of the carabiner when I'm hanging on it 71 00:03:44,270 --> 00:03:46,050 are being spread apart, 72 00:03:46,050 --> 00:03:49,850 but they like to stay together, so they pull back. 73 00:03:49,850 --> 00:03:52,520 You can't see this expansion of the *carabiner 74 00:03:52,520 --> 00:03:56,123 on low forces, but you can on big ones. 75 00:04:02,210 --> 00:04:04,870 And so it turns out that this carabiner 76 00:04:04,870 --> 00:04:08,080 has to accelerate my weight up 77 00:04:08,080 --> 00:04:12,680 at the same 9.8 meters per second squared, 78 00:04:12,680 --> 00:04:16,290 which turns out to be about 600 Newtons. 79 00:04:16,290 --> 00:04:21,290 Yep, 600 of these need to hold one skinny guy like me. 80 00:04:28,800 --> 00:04:32,210 Okay, moving on, this carabiner says 81 00:04:32,210 --> 00:04:37,210 that it can hold up to 26 kilonewtons. 82 00:04:37,567 --> 00:04:41,000 Kilonewton is basically a thousand Newtons. 83 00:04:41,000 --> 00:04:45,483 So it means that it could hold about 40 me. 84 00:04:46,650 --> 00:04:48,610 I wish I would have a clone machine, 85 00:04:48,610 --> 00:04:50,763 so I could demonstrate this to you. 86 00:04:52,520 --> 00:04:57,520 Then imagine how many videos all of these me could create. 87 00:04:57,958 --> 00:05:01,040 (bright music) 88 00:05:01,040 --> 00:05:05,870 So if you wanna see us create more videos like this, 89 00:05:05,870 --> 00:05:09,150 click the join button, it really helps. 90 00:05:09,150 --> 00:05:12,050 And I promise I will spend every single penny 91 00:05:12,050 --> 00:05:15,699 I get from you guys on buying a clone machine. 92 00:05:15,699 --> 00:05:17,349 Enjoy. 93 00:05:17,349 --> 00:05:22,180 (chuckling) Okay, so you can hang 40 me 94 00:05:22,180 --> 00:05:26,570 on one single carabiner, that's pretty impressive. 95 00:05:26,570 --> 00:05:29,520 Although there are things that you must know. 96 00:05:29,520 --> 00:05:31,950 First of all, all of these ratings 97 00:05:31,950 --> 00:05:33,980 are for new equipment, 98 00:05:33,980 --> 00:05:37,510 wear and tear does not go into that rating. 99 00:05:37,510 --> 00:05:39,190 How bad is that? 100 00:05:39,190 --> 00:05:42,686 Well, I asked my friend, Ryan from YouTube channel, 101 00:05:42,686 --> 00:05:45,770 HowNOTtoHighline because he has a hobby 102 00:05:45,770 --> 00:05:47,870 of breaking stuff. 103 00:05:47,870 --> 00:05:50,200 And according to his tests, 104 00:05:50,200 --> 00:05:53,490 most of the metals tend to last pretty well. 105 00:05:53,490 --> 00:05:58,490 Although with soft things, things are totally different. 106 00:05:58,740 --> 00:06:02,033 - [Ryan] Black Diamond sling with a 22 kilonewton MBS. 107 00:06:03,089 --> 00:06:04,313 (machine whirs) 108 00:06:04,313 --> 00:06:07,063 (metallic clang) 109 00:06:09,071 --> 00:06:12,770 What? Was the MBS on 22 kilonewtons? 110 00:06:12,770 --> 00:06:13,603 - [Man] Yeah. 111 00:06:13,603 --> 00:06:18,300 - Yep, a sling rated at 22 kilonewtons broke at six. 112 00:06:19,490 --> 00:06:20,670 And here is another one. 113 00:06:20,670 --> 00:06:24,970 - [Ryan] Woo, that's a great condition. 114 00:06:24,970 --> 00:06:26,193 - [Man] Would not whip. 115 00:06:27,580 --> 00:06:28,723 - [Ryan] No, not whip. 116 00:06:30,270 --> 00:06:32,000 I would tie my dog to this though. 117 00:06:32,000 --> 00:06:34,667 (machine whirs) 118 00:06:36,912 --> 00:06:38,042 All right. 119 00:06:38,042 --> 00:06:40,417 - [Man] I wouldn't tie a very big dog with that. 120 00:06:40,417 --> 00:06:44,640 - [Ryan] (giggling) All right, let's see how big of a dog 121 00:06:44,640 --> 00:06:47,470 could you have tied with this? 122 00:06:47,470 --> 00:06:49,740 Ooh, a Chihuahua. 123 00:06:49,740 --> 00:06:50,690 (man chuckles) 124 00:06:50,690 --> 00:06:53,250 - Yeah, so if you're one of these people 125 00:06:53,250 --> 00:06:56,330 who like to save money and use very old, 126 00:06:56,330 --> 00:06:58,780 worn down slings, good luck. 127 00:06:58,780 --> 00:07:00,345 - [Ryan] 24 kilonewtons, 128 00:07:00,345 --> 00:07:03,012 (machine whirs) 129 00:07:04,067 --> 00:07:05,580 that did not stretch that much. 130 00:07:05,580 --> 00:07:08,286 Oh, guess, guess. 131 00:07:08,286 --> 00:07:09,119 - [Man] I saw. 132 00:07:09,119 --> 00:07:13,440 - [Ryan] Four kilonewtons, what the fuck, man? 133 00:07:13,440 --> 00:07:18,440 - 4,000 Newtons, okay how much does such sling can hold? 134 00:07:19,420 --> 00:07:20,660 Well, that's pretty easy. 135 00:07:20,660 --> 00:07:24,700 Just divide 4,000 Newtons by 9.8. 136 00:07:24,700 --> 00:07:29,700 Or if you want easier, by 10 and you get 400 kilograms. 137 00:07:29,870 --> 00:07:32,763 That sounds quite a lot. No? 400 kilograms? 138 00:07:33,940 --> 00:07:38,940 Well, all of these conversions from force to kilograms 139 00:07:38,950 --> 00:07:41,270 that I have been talking so far 140 00:07:41,270 --> 00:07:45,690 are based on the fact that the weight is hanging statically. 141 00:07:45,690 --> 00:07:49,541 Once the thing starts falling, everything changes. 142 00:07:49,541 --> 00:07:50,425 - [Man] Go. 143 00:07:50,425 --> 00:07:53,800 (metallic clanking) 144 00:07:53,800 --> 00:07:56,840 - So what you have just seen is a clip from DMM, 145 00:07:56,840 --> 00:07:59,900 where they dropped 80 kilograms of mass, 146 00:07:59,900 --> 00:08:03,510 and that broke a brand new Dyneema sling. 147 00:08:03,510 --> 00:08:06,590 Now my goal is not to scare you, it's the opposite. 148 00:08:06,590 --> 00:08:09,520 I want to bring the awareness that climbing gear 149 00:08:09,520 --> 00:08:14,393 is not magic, and if you use it incorrectly, it might fail. 150 00:08:16,600 --> 00:08:19,350 Fun fact, do you know this joke that climbers 151 00:08:19,350 --> 00:08:21,830 like to say when they fail on their climbs? 152 00:08:21,830 --> 00:08:24,890 That today is a high gravity day. 153 00:08:24,890 --> 00:08:27,070 Well, turns out that's true, 154 00:08:27,070 --> 00:08:30,200 gravity does change from month to month. 155 00:08:30,200 --> 00:08:32,580 So if you are one of those people 156 00:08:32,580 --> 00:08:35,830 who like to complain that today is a bad humidity, 157 00:08:35,830 --> 00:08:38,760 or bad temperature, now you have a right to complain 158 00:08:38,760 --> 00:08:41,690 that today's a bad gravity day, yay! 159 00:08:41,690 --> 00:08:43,950 Okay, let's see what happens 160 00:08:43,950 --> 00:08:47,873 when objects like us, climbers, start falling. 161 00:08:51,100 --> 00:08:54,090 That was a 10 meters fall. 162 00:08:54,090 --> 00:08:56,070 Let's see how much force such fall 163 00:08:56,070 --> 00:08:58,010 would generate to the climber. 164 00:08:58,010 --> 00:09:00,210 The formula for that would be similar 165 00:09:00,210 --> 00:09:03,540 to what we had before, except that we need to multiply 166 00:09:03,540 --> 00:09:07,010 this by the distance the climber was falling, 167 00:09:07,010 --> 00:09:11,123 and divide by the distance the climber was slowing down. 168 00:09:16,870 --> 00:09:18,340 And did you actually notice 169 00:09:18,340 --> 00:09:20,933 how soft the fall for the climber was? 170 00:09:23,200 --> 00:09:26,460 So imagine driving a car in a highway, 171 00:09:26,460 --> 00:09:31,460 and pressing on the brake gently while you come to a stop. 172 00:09:31,620 --> 00:09:33,110 No problems right? 173 00:09:33,110 --> 00:09:35,090 Now imagine you are not driving so fast, 174 00:09:35,090 --> 00:09:37,650 you're in a city, you're driving slowly, 175 00:09:37,650 --> 00:09:39,043 but you slam on the brake, 176 00:09:40,200 --> 00:09:43,370 that would not feel very nice, right? 177 00:09:43,370 --> 00:09:45,700 So here is the first thing I want you to remember 178 00:09:45,700 --> 00:09:48,820 out of this video, the impact to the climber 179 00:09:48,820 --> 00:09:51,660 will always be multiplied by the distance 180 00:09:51,660 --> 00:09:54,990 the climber was falling, divided by the distance 181 00:09:54,990 --> 00:09:57,360 of the slow down phase. 182 00:09:57,360 --> 00:10:00,100 So let's calculate, their falling distance 183 00:10:00,100 --> 00:10:02,300 was about four quickdraws, 184 00:10:02,300 --> 00:10:04,573 and their slowdown distance was about 185 00:10:04,573 --> 00:10:06,630 two and a half quickdraws. 186 00:10:06,630 --> 00:10:09,480 And we get about 860 Newtons. 187 00:10:09,480 --> 00:10:12,360 Or if we would replace her with a standard 188 00:10:12,360 --> 00:10:17,360 80 kilogram climber, that would be about 1.3 kilonewtons, 189 00:10:18,490 --> 00:10:19,910 which is not much. 190 00:10:19,910 --> 00:10:22,210 Although this formula has a little problem 191 00:10:22,210 --> 00:10:26,470 because it will always give you the value of it just slightly lower 192 00:10:26,470 --> 00:10:28,810 than it would be in real life. 193 00:10:28,810 --> 00:10:31,718 But showing you how to calculate more precisely 194 00:10:31,718 --> 00:10:33,970 would mean that most of you would probably 195 00:10:33,970 --> 00:10:35,950 just leave this video right here. 196 00:10:35,950 --> 00:10:37,830 But we don't need to do that, 197 00:10:37,830 --> 00:10:41,630 because we can rely on real life experimental data. 198 00:10:41,630 --> 00:10:44,810 And who is the boss at providing such data for us? 199 00:10:44,810 --> 00:10:46,180 - Hi, I'm Ryan Jenks and- 200 00:10:46,180 --> 00:10:49,260 - And then that's enough advertisement for you. 201 00:10:49,260 --> 00:10:50,750 What they did in this video, 202 00:10:50,750 --> 00:10:54,440 they put a device measuring the force on the climber, 203 00:10:54,440 --> 00:10:56,633 and made a series of falls. 204 00:10:58,859 --> 00:11:00,743 - (laughing) Zach. 205 00:11:07,410 --> 00:11:09,143 For science, woo hoo. 206 00:11:12,978 --> 00:11:14,728 That puts me at 1.87. 207 00:11:15,950 --> 00:11:18,190 - So most of the falls, that in my opinion, 208 00:11:18,190 --> 00:11:20,340 would be a good belaying example, 209 00:11:20,340 --> 00:11:22,710 were below two kilonewtons. 210 00:11:22,710 --> 00:11:26,430 Now let's take a look at these two extreme examples. 211 00:11:26,430 --> 00:11:29,560 Climber on the left is five meters above the bolt, 212 00:11:29,560 --> 00:11:31,950 so that would be 10 meters fall 213 00:11:31,950 --> 00:11:34,030 plus the slack in the system. 214 00:11:34,030 --> 00:11:37,090 The belayer probably has about one meter of slack. 215 00:11:37,090 --> 00:11:40,150 And then there is probably one more meter of slack 216 00:11:40,150 --> 00:11:41,590 in between the quickdraws. 217 00:11:41,590 --> 00:11:44,970 So in total, we are looking at 12 meters fall. 218 00:11:44,970 --> 00:11:48,470 While climber on the right is only one meter above the bolt. 219 00:11:48,470 --> 00:11:51,320 And let's say that belayer is really afraid, 220 00:11:51,320 --> 00:11:54,660 and he's going to give a very hard catch for the climber. 221 00:11:54,660 --> 00:11:57,183 So we are looking at two meters fall. 222 00:11:58,040 --> 00:12:03,040 So a massive 12 meters fall, or a small two meters fall. 223 00:12:03,090 --> 00:12:06,440 Which one do you think is going to be softer for the climber? 224 00:12:06,440 --> 00:12:08,420 Well, let's see, we know how much 225 00:12:08,420 --> 00:12:11,440 the climbers will fall. But now we need to find out 226 00:12:11,440 --> 00:12:14,880 the slowed down distances for both of the cases. 227 00:12:14,880 --> 00:12:17,700 And that depends mainly on two things. 228 00:12:17,700 --> 00:12:20,580 First is the displacement of the belayer. 229 00:12:20,580 --> 00:12:24,090 On a big, big whipper, the belayer will probably fly 230 00:12:24,090 --> 00:12:27,220 about two meters, while on a small fall, 231 00:12:27,220 --> 00:12:30,110 let's assume very common mistake for beginners, 232 00:12:30,110 --> 00:12:32,560 where the belayer just takes the slack out 233 00:12:32,560 --> 00:12:34,430 and belays very hard. 234 00:12:34,430 --> 00:12:38,210 And the second factor is the stretch of the rope. 235 00:12:38,210 --> 00:12:41,430 Rope manufacturers claim that if you put 80 kilogram 236 00:12:41,430 --> 00:12:44,700 mass on a dynamic rope statically, 237 00:12:44,700 --> 00:12:49,160 like so, without movement, the rope will stretch 10%. 238 00:12:49,160 --> 00:12:52,600 And dynamic stretch, when you take a lead fall, 239 00:12:52,600 --> 00:12:55,440 is up to 30%. 240 00:12:55,440 --> 00:12:58,550 Well up to 30% is not very helpful for us. 241 00:12:58,550 --> 00:13:01,590 What we need to know is the stretch of this rope 242 00:13:01,590 --> 00:13:04,530 from two to four kilonewtons force, 243 00:13:04,530 --> 00:13:06,810 that's where the lead falls are. 244 00:13:06,810 --> 00:13:09,250 And yet again, I was texting Ryan. 245 00:13:09,250 --> 00:13:11,280 - So, I'm gonna pull some dynamic rope, 246 00:13:11,280 --> 00:13:12,820 to see how much it stretches. 247 00:13:12,820 --> 00:13:14,928 At first, we thought it's gonna be very easy, 248 00:13:14,928 --> 00:13:17,990 just go to the park, stretch the rope to different forces, 249 00:13:17,990 --> 00:13:21,110 and measure the elongation of the rope. 250 00:13:21,110 --> 00:13:24,660 Well, sometimes easy is hard. 251 00:13:24,660 --> 00:13:27,570 When you stretch the rope to certain force 252 00:13:27,570 --> 00:13:30,120 and leave it there, the force will start 253 00:13:30,120 --> 00:13:33,580 dropping on the rope, the rope kind of just gives up. 254 00:13:33,580 --> 00:13:36,890 While this is very interesting, it's not critical for us. 255 00:13:36,890 --> 00:13:39,500 The only thing he needed to do is to pull the rope 256 00:13:39,500 --> 00:13:42,390 as fast as he can to desired force, 257 00:13:42,390 --> 00:13:44,290 and measure the stretch. 258 00:13:44,290 --> 00:13:49,290 - [Ryan] Okay, oh my God, that's the seven mark... 259 00:13:49,610 --> 00:13:55,490 6.9 meters... it stretches... when you pull it... 260 00:13:55,630 --> 00:13:59,380 a dynamic rope... to four kilonewtons. 261 00:13:59,380 --> 00:14:01,480 But then there is another interesting factor, 262 00:14:01,480 --> 00:14:04,200 once you load the rope to high forces, 263 00:14:04,200 --> 00:14:06,090 it takes some time for the rope 264 00:14:06,090 --> 00:14:08,590 to get back to its original length. 265 00:14:08,590 --> 00:14:11,490 This is what's known as rope resting, 266 00:14:11,490 --> 00:14:13,810 and it was really cool to see this in action. 267 00:14:13,810 --> 00:14:16,913 - [Ryan] See the Grigri getting pulled back slowly? 268 00:14:19,540 --> 00:14:22,838 Super interesting, probably way more interesting 269 00:14:22,838 --> 00:14:25,260 to me than it is to you right now. 270 00:14:25,260 --> 00:14:27,860 So after he spent like four hours in the park 271 00:14:27,860 --> 00:14:31,460 pulling the ropes, the results were that on forces 272 00:14:31,460 --> 00:14:33,890 from two to four kilonewtons, 273 00:14:33,890 --> 00:14:37,750 the rope stretched to about 20%. 274 00:14:37,750 --> 00:14:41,180 Great, so let's use that in our calculations. 275 00:14:41,180 --> 00:14:45,240 On a big fall, we have 27 meters of rope in total, 276 00:14:45,240 --> 00:14:49,570 so that would be 5.4 meters of stretch. 277 00:14:49,570 --> 00:14:52,600 While in a small fall, we have five meters of rope, 278 00:14:52,600 --> 00:14:54,940 and that would be one meter of stretch. 279 00:14:54,940 --> 00:14:58,600 However, our belayer is panicking and taking hard, 280 00:14:58,600 --> 00:15:02,170 so he will take half of that stretch for himself, 281 00:15:02,170 --> 00:15:06,540 leaving only half a meter of stretch for the climber. 282 00:15:06,540 --> 00:15:09,660 And ta-da, the big, big whipper 283 00:15:09,660 --> 00:15:13,580 will be two and a half times softer for the climber 284 00:15:13,580 --> 00:15:15,113 than the small fall. 285 00:15:16,470 --> 00:15:17,870 Oh, I love fun facts, 286 00:15:17,870 --> 00:15:19,180 here is another one. 287 00:15:19,180 --> 00:15:21,830 Imagine that you were climbing and failed, 288 00:15:21,830 --> 00:15:25,370 but humidity was good, temperature was good, 289 00:15:25,370 --> 00:15:27,483 even the gravity was good that day. 290 00:15:28,370 --> 00:15:30,030 You can still blame the moon. 291 00:15:30,030 --> 00:15:33,330 - [Narrator] Negligibly but truly, 292 00:15:33,330 --> 00:15:36,460 you weigh about a million of your weight less 293 00:15:36,460 --> 00:15:38,740 when the moon is directly above you. 294 00:15:38,740 --> 00:15:41,360 - So if you wanna ascend, climb when the moon 295 00:15:41,360 --> 00:15:45,520 is directly above you, you're welcome. 296 00:15:45,520 --> 00:15:48,360 I remember I was projecting this really long route 297 00:15:48,360 --> 00:15:52,010 of 35 meters, and the first time I managed to link 298 00:15:52,010 --> 00:15:54,707 all the cruxes and arrive at the anchor, 299 00:15:54,707 --> 00:15:57,300 the moment when I was pulling the rope up 300 00:15:57,300 --> 00:15:58,650 to clip the anchor, 301 00:15:58,650 --> 00:16:00,810 my belayer couldn't see me very well, 302 00:16:00,810 --> 00:16:03,300 so he just gave me a lot of slack. 303 00:16:03,300 --> 00:16:06,930 And on top of that, the bolt before the anchor 304 00:16:06,930 --> 00:16:10,230 was really far, really ran out. 305 00:16:10,230 --> 00:16:12,800 So while I was dragging the rope up, 306 00:16:12,800 --> 00:16:15,720 I lost my balance and took a fall. 307 00:16:15,720 --> 00:16:17,510 The wall is flying in front of me, 308 00:16:17,510 --> 00:16:20,140 and I'm thinking, "Why I'm still falling? 309 00:16:20,140 --> 00:16:21,930 Hmm, this is unusual." 310 00:16:21,930 --> 00:16:23,470 Then I stopped and looked up, 311 00:16:23,470 --> 00:16:25,970 it was maybe five or six Quickdraws above me, 312 00:16:25,970 --> 00:16:29,390 probably about 15 meters of fall. 313 00:16:29,390 --> 00:16:34,320 But the fall was super soft, it's like riding an elevator. 314 00:16:34,320 --> 00:16:36,860 So here is another takeaway out of this video, 315 00:16:36,860 --> 00:16:39,130 if the climber is really high up, 316 00:16:39,130 --> 00:16:41,700 he has a lot of rope to absorb the fall. 317 00:16:41,700 --> 00:16:44,930 So as long as he doesn't fall onto something, 318 00:16:44,930 --> 00:16:49,220 the fall will be soft, no matter how you belay that. 319 00:16:49,220 --> 00:16:51,960 However, if the climber is not so high, 320 00:16:51,960 --> 00:16:54,790 he doesn't have so much rope to absorb the fall, 321 00:16:54,790 --> 00:16:59,680 The soft dynamic delaying is really important, 322 00:16:59,680 --> 00:17:02,050 and you can ask any light climber, 323 00:17:02,050 --> 00:17:05,620 how many times they had their ankles broken 324 00:17:05,620 --> 00:17:07,550 due to hard catches. 325 00:17:07,550 --> 00:17:09,300 Okay, let's switch gears a little bit. 326 00:17:09,300 --> 00:17:11,300 Let's talk about friction, 327 00:17:11,300 --> 00:17:13,710 'cause the more friction you have, 328 00:17:13,710 --> 00:17:17,000 the harder the fall for the climber will be. 329 00:17:17,000 --> 00:17:19,540 And here is a very extreme example of that. 330 00:17:19,540 --> 00:17:23,730 - As you can see right here, we Z dragged it. 331 00:17:23,730 --> 00:17:27,560 And so we're gonna have a lot of friction when I fall. 332 00:17:27,560 --> 00:17:29,241 And whoo, for science. 333 00:17:29,241 --> 00:17:30,541 Do it! 334 00:17:30,541 --> 00:17:31,374 Oh my God! 335 00:17:34,280 --> 00:17:36,330 - So when you have a lot of friction, 336 00:17:36,330 --> 00:17:39,740 the rope close to the climber stretches normally, 337 00:17:39,740 --> 00:17:43,960 but the rope closer to belayer doesn't stretch that much. 338 00:17:43,960 --> 00:17:46,770 It's like having shorter rope and heavier belayer 339 00:17:46,770 --> 00:17:47,820 at the same time. 340 00:17:47,820 --> 00:17:50,230 And although the force to the harness 341 00:17:50,230 --> 00:17:52,500 was only two and a half kilonewtons, 342 00:17:52,500 --> 00:17:55,918 a lot of the force went pendulum into the wall. 343 00:17:55,918 --> 00:17:57,330 - Do it. 344 00:17:57,330 --> 00:17:59,530 - And that's how we break ankles. 345 00:17:59,530 --> 00:18:03,410 So extending the Quickdraws not only helps you to clip 346 00:18:03,410 --> 00:18:05,286 and avoid situations like this, 347 00:18:05,286 --> 00:18:06,119 (upbeat music) 348 00:18:06,119 --> 00:18:09,119 (climber straining) 349 00:18:16,650 --> 00:18:20,650 But also reduces the impact forces for the climbers. 350 00:18:20,650 --> 00:18:23,930 Okay, let's circle back to the DMM test, 351 00:18:23,930 --> 00:18:25,720 breaking the sling. 352 00:18:25,720 --> 00:18:29,730 Dyneema slings are very static, they don't stretch at all. 353 00:18:29,730 --> 00:18:31,520 And I hope that by now you understand 354 00:18:31,520 --> 00:18:34,980 that this sudden stop can create huge forces. 355 00:18:34,980 --> 00:18:37,600 If not, ask somebody to slap you. 356 00:18:37,600 --> 00:18:40,650 This stop on the face will be basically 357 00:18:40,650 --> 00:18:41,950 what you need to understand. 358 00:18:41,950 --> 00:18:43,860 So let's make a very wild 359 00:18:43,860 --> 00:18:46,230 and probably very inaccurate guess 360 00:18:46,230 --> 00:18:51,160 that this sling would stretch to about five centimeters. 361 00:18:51,160 --> 00:18:54,590 So if we drop 80 kilograms of mass, 362 00:18:54,590 --> 00:18:57,980 the distance of 120 centimeters, 363 00:18:57,980 --> 00:19:01,960 and the absorption distance is only five centimeters, 364 00:19:01,960 --> 00:19:06,160 we are looking at 19 kilonewtons. 365 00:19:06,160 --> 00:19:08,850 If that is not gonna break the sling, 366 00:19:08,850 --> 00:19:11,990 it's definitely gonna break you. 367 00:19:11,990 --> 00:19:14,070 Woo, if you're still watching, 368 00:19:14,070 --> 00:19:16,030 that probably means that you should be 369 00:19:16,030 --> 00:19:18,440 at least a little bit geeky. 370 00:19:18,440 --> 00:19:20,443 So here is a dessert for you. 371 00:19:21,320 --> 00:19:23,840 There is no gravity. 372 00:19:23,840 --> 00:19:27,120 Yeah, objects don't attract each other, 373 00:19:27,120 --> 00:19:28,880 there is only space time. 374 00:19:28,880 --> 00:19:31,800 - You feel as though you're being pushed into the ground, 375 00:19:31,800 --> 00:19:34,110 not because of a force called gravity, 376 00:19:34,110 --> 00:19:36,360 but because time is moving faster 377 00:19:36,360 --> 00:19:38,890 for your head than for your feet. 378 00:19:38,890 --> 00:19:41,440 - This and all the other resources that I use 379 00:19:41,440 --> 00:19:44,590 to create this video will be in the description. 380 00:19:44,590 --> 00:19:47,280 And now please go send some love to Ryan 381 00:19:47,280 --> 00:19:50,460 for providing me with all of his experimental data 382 00:19:50,460 --> 00:19:52,360 that I used in this video. 383 00:19:52,360 --> 00:19:55,460 So don't forget to subscribe and support our channels 384 00:19:55,460 --> 00:19:57,960 if you wanna see more content like this. 385 00:19:57,960 --> 00:19:58,793 Enjoy.