## Written By: Lance Piatt

`Full Video is at the bottom`

A force multiplier is any factor or condition that contributes to the overall stress of a rope system during a dynamic state. Rating this dynamic state or rope movement/stress is best represented as the Dynamic System Safety Factor (DSSF). In other words, what’s our weakest link during the operation of our rope system at its point of greatest stress, typically during the onset of a hauling process.

During the course of this unit, we’ll examine five areas of misunderstanding in rope rigging commonly seen with emergency responders in the urban technical rescue environment:

1. Force Vectors
2. Tensile Force
3. Compression Force
4. Friction
5. And torque

The discussion will center around Unit-less ValuesScalars, and Vectors. These are essentially escalating terms and incorporate all the common aspects of we “think about” in terms of rigging a system. As you’ll see, there’s a lot going on!

So, I want to be really clear about the difference between unitless values, scalars and vectors.

Now, most people are already familiar with broadly what we mean by a vector, because we’re talking about resultant forces. But I need to just divide those three up a little bit. So unitless values are typically things like ratios. An example of a ratio is the mechanical advantage that we look at with systems. I don’t normally say that the mechanical advantage of that system is three-to-one feet, or three-to-one hours. It’s just three to one, we don’t have any units that we tack on the end of that description. So that’s a unitless value.

Another example of such a ratio is the number Pi, or something like 3.14159. We never put units on the end of that because it technically is the ratio between the diameter and the circumference of a circle. And whatever we measure that diameter in, centimeters, then we would put the Pi in there and we get an answer that’s in centimeters. So we don’t put a unit with the number Pi, because it is a ratio.

The next thing, if we do start to associate values, if we’re talking about measuring the length of things, so I can say to someone, “How long is that pen?” And then I can get a ruler and put it there and measure it. And I might get that that’s 15 centimeters. That unit on the end is important, because if I just said 15 and then wrote that down, it’s a pen that’s 15 long. Someone else might read that and say, “Well, is that centimeters or is it inches? Or … ” And they have to guess. So we’ve got to be quite specific when we’re measuring things like that, which is why we put units like centimeters.

So a scalar only has a dimensional unit that we associate with it. Vectors, now, are the next step in that process. When we measure vectors, we don’t just need to measure how many or how far or how long. We also need to say what direction, where we’re going to be applying that effort or that distance.

Now a good example, just to distinguish between a scalar value and a vector quantity is if we’re talking about traveling. So I can say that I’ve just traveled a distance of two miles. That would be a scalar measurement of distance. The vector equivalent of that, we would describe as displacement.

And if I want to talk about that as a displacement, I don’t just say I’ve traveled two miles, but I might say that I’ve traveled two miles heading due north. And that way, if I’ve got someone describing on a radio their journey, they might say they’ve gone two miles due north, and then they’ve gone one mile east. And that enables me to work out exactly where their position is because I can go up two miles and across one. And on the map, I can plot their position, which gives me a final vector displacement from here to this point.

So the vectors and that description of magnitude and direction are really important when we’re talking about analyzing the forces in the systems that we’re going to be working with.

Let’s consider one such system. And it might be a typical … If it’s a rope access context, a Y hang anchor, where we would have, and I’ll just go to the tablet here. I might have one anchor point in this position here, and I might have another anchor point here. And then I’m going to set up my roping system so that it’s attached to both of these anchors. I’ll have some connector or some knot system here. And then I might have my load suspended below on that rope based system.

When we’re working out our resultant forces and the way we distribute the loads, or attribute the amount of tension in each of these anchor legs as a result of this load being applied to the system, we’ve got directions that are actually defined by each of these anchor legs in the system.

Another example where we’re looking at forces is if I have an object at rest on a surface. So it might be a block of steel at rest on a nylon surface, for example. We spoke about weight before. That block of steel is exerting a downwards force on that surface that it’s resting on. It might, for argument’s sake, have a weight of one kilo-Newton, 220 pounds if it’s a static mass, or a hundred kilograms. If I want to move that block, I need to apply a force in a particular direction. And I might apply a force of 0.5 kilo-Newtons from behind the block to try and start moving that along.

Now, if I want to analyze what’s going to happen with that movement, I need to consider all the forces acting on that block. Another force is friction, and we’ll be talking a lot about friction as part of this series. So I can now consider that block … I’m going to be applying this external force from behind, I’ve got the weight here, and I’ve got the friction between those two surfaces. I need to consider all of those before I can start to work at how that’s going to move.

The other place where this will become significant is we look at the ratings of the equipment that we’re using as rope technicians. They’re typically rated in terms of kilo-Newtons, as either a working load limit or a safe working load, or an MBS. And we need to know how to interpret that stuff. If a carabiner is rated to 30 kilo-Newtons, we need to be able to work out, “What does that mean in terms of suspending a static mass from that carabiner?”

Here we are looking at weight and its relationship with mass, you might remember from school, force equals mass times acceleration. Now, how does that apply to weight? Well, weight is a force. And when we’ve got someone on the Earth, they’re subjected to the acceleration due to gravity on Earth, which is 9.81 meters per second squared. That’s the rate at which, if I drop something, it will accelerate towards the center of the Earth, if it’s unimpeded.

So if we consider a person with a mass of 100 kilograms, and they’re positioned on the Earth, their weight applied towards the center of the Earth, we can calculate by saying, “Weight equals mass times the acceleration due to gravity.” We know their mass is 100 kilograms, the acceleration due to gravity is 9.81 meters per second squared, so we come up with a weight of 981 Newtons.

Now those sort of numbers are hard to work with in the field, so typically we’ll make an approximation, and say rather than 9.81, let’s call that 10, which means then we can say that their weight is approximately equal to one kilo-Newton. I just did a little trick there, or a little sleight of hand. A thousand Newtons is the same as that one kilo-Newton.

Now just reinforcing that position that my mass stays the same, regardless of where I am, because mass is just a function of volume and density, if I take that same person and take them to the Moon … Their mass remains the same. However, the acceleration due to gravity on the moon is only 1.62 meters per second squared. So that means if I run these same calculations, the weight of that same person on the Moon is only 162 Newtons rather than a thousand Newtons. It’s less than a fifth. So the mass remains the same, but the weight is quite different.

So that consideration of forces, we’re going to move forwards with in every part of the next units that we’re looking at in this presentation: the force that we’re applying to static systems, and the forces that we’re going to be applying to dynamic systems.

Lance

### 3,760 thoughts on “Vectors, Scalars, and Unit-less Values, Part 1”

1. Fantastic blog you have here but I was wanting to know if you knew of any community forums that cover the same
a part of group where I can get comments from other knowledgeable individuals that share the
same interest. If you have any recommendations, please let me know.
Many thanks!

2. Nice post. I learn something totally new and challenging on sites I stumbleupon everyday. It will always be helpful to read articles from other writers and use something from other sites.

3. Hi, i think that i saw you visited my web site thus i came to “return the favor”.I am attempting to
find things to improve my site!I suppose its ok to use some of your ideas!!

4. כל בחורה אוהבת לקבל מסאז’ מהגבר שלה- בגב, בכתפיים,
באזור הצוואר והראש. בקרו בפורטל,
בחרו את המודעה המתאימה לכם, עשו את סקר השווקים האחרון וצאו לדרך מלאה בהנאות
ורוויה בהגשמת כל הפנטזיות הלוהטות
עליהן חלמתם. תמיד רציני לנייש
אבל לא היה קל למצוא את המתאים.

כאשר למשל אתם נוסעים לנופש באיזה צימר מפנק,
או בית מלון, תמיד תחשבו ישר על הפינוק של עצמכם ותזמינו עיסוי,
כי אם כבר אז כבר. תוכלו להגיע לבד אם הינכם מעוניינים בשקט
והפוגה מעולמכם הרועש, וכן תוכלו להגיע עם בן או בת זוג אהובים לבילוי רומנטי משותף.
מסאג לומי לומי,טיפול עם דבש ושמנים ארומטים.
דירה דיסקרטית כאמור זהו ״דירת מבטחים״ בה תוכל
להיפגש עם מטפלות האהובות עליך, הרצויה
לך, זאת שנמצאת בדירה דיסקרטית בקריות ובכלל, זאת
דירה בה המעסה האירוטית מתגוררת או בה היא עובדת.
מחפשים באתר בחורה בדירה דיסקרטית
בקריות והנה לך ערב סקסי שקט וחופשי מדאגות.

בחורה פרטית, מחכה לך בדירה
דיסקרטית שהיא…

5. Right here is the right blog for anyone who would like to find out about this
topic. You know a whole lot its almost hard to argue with you (not that I personally will need to…HaHa).
You certainly put a new spin on a topic that
has been discussed for decades. Wonderful stuff, just excellent!

6. Thanks-a-mundo for the blog post.Really looking forward to read more.

7. I’m gone to say to my little brother, that he should also pay a quick visit this blog on regular basis to obtain updated
from latest information.

8. Hmm it looks like your site ate my first comment (it was super long)
so I guess I’ll just sum it up what I wrote and say, I’m thoroughly
enjoying your blog. I as well am an aspiring blog writer but I’m still new to the
whole thing. Do you have any suggestions for first-time blog writers?
I’d genuinely appreciate it.

9. My partner and I absolutely love your blog and find the majority of
your post’s to be precisely what I’m looking for.

Does one offer guest writers to write content for yourself?
I wouldn’t mind creating a post or elaborating on many of
the subjects you write related to here. Again, awesome
web site!

10. I think the admin of this website is truly working hard for his web site, because here every data is quality based data.

11. Write more, thats all I have to say. Literally, it seems as though you relied on the video to make your point.
You definitely know what youre talking about, why throw away your intelligence on just posting videos to your weblog
when you could be giving us something informative to read?

12. Hey! I could have sworn I’ve been to this site before but after checking through some of the post I realized it’s new to me.
Anyhow, I’m definitely glad I found it and I’ll be bookmarking and
checking back often!

in it or something. I think that you can do with some pics to drive the message home a little bit,
but other than that, this is excellent blog.
A fantastic read. I’ll certainly be back.

14. You actually make it seem so easy with your presentation but I find this topic to
be actually something that I think I would never understand.
It seems too complex and very broad for me. I am looking forward for your next post, I’ll
try to get the hang of it!

15. I loved as much as you’ll receive carried out right here.
The sketch is tasteful, your authored subject matter stylish.
nonetheless, you command get bought an edginess over that you wish be delivering the following.
unwell unquestionably come more formerly again as exactly the same nearly very
often inside case you shield this hike.

16. This is very interesting, You are an overly professional blogger.
I have joined your rss feed and stay up for searching for more of your
fantastic post. Also, I’ve shared your website in my
social networks

17. Dołącz do grona zadowolonych graczy i korzystaj z najlepszych i najnowszych promocji hazardowych bezdepozytu. Poznawaj nowe polskie kasyno online bonus bez depozytu, testuj premierowe sloty i korzystaj z promocji przygotowanych dla aktywnych graczy. Información importante Jeżeli chcesz dostać Vulkan Bet darmowe spiny bez depozytu, to zaraz po wykonaniu tych kroków uzyskasz na początek Swojej zabawy 50 darmowych spinów na grę Hot Triple Sevens (Evoplay). Należy działać zgodnie z regulaminem, żeby spełnić wszystkie wymagania i darmowe obroty nie zostały stracone: Dbając o różnorodność i kompleksować oferty, w Vulkan Vegas Casino współpracujemy z mnóstwem dostawców oprogramowania do gier hazardowych. Pośród nich pojawią się najwybitniejsi i najzdolniejsi twórcy gier hazardowych online. https://training-schoolstarter.eu/community/profile/louellamoffatt0/ 18.45 – Pierwsze efekty DXM Dlatego zawsze powtarzam (i na tej podstawie, zrobiono ze mnie obłąkanego obrońcę Dutkiewicza), że w procesie budowlanym na słabe przygotowanie merytoryczne Zamawiającego nakłada się dzika chęć zysku (co powoduje problemy takie jak w Poznaniu) Wykonawcy i za problemy z jakością, terminowością, kosztownością prac odpowiedzialne są obie strony tego procesu (a jak jeszcze jest gówniany nadzór, to już zupełnie mamy lipę). Przecież Hydrobudowę na placu budowy nadzorował za grube pieniądze Nadzór Inwestorski. Jeśli Hydrobudowa padła to w normalnym kraju, roszczenia powinny zostać przeniesione na NI. Jak mówi sam Homme: „najważniejszym aspektem tego albumu była próba przedefiniowania naszego brzmienia. Próba zadania i odpowiedzenia sobie na pytanie „jak powinniśmy brzmieć dzisiaj?”. Jeśli nie możesz nagrać znakomitej pierwszej płyty, powinieneś się zatrzymać. Jednak jeśli możesz nagrywać świetne płyty, ale twoje brzmienie nie ewoluuje, staje się to parodią oryginalnego brzmienia”. Ich kolejna odsłona z płyty nosi tytuł „Feet Don’t Fail Me”.

18. My brother recommended I might like this website. He was totally right.
This post truly made my day. You can not imagine just how
much time I had spent for this info! Thanks!

19. I got this web site from my friend who informed me concerning this site and at the moment this time I am visiting this site and reading very informative articles or reviews here.

20. I just could not leave your website prior to suggesting that I actually
loved the standard info a person supply for your guests?
Is gonna be back frequently to check out new posts

21. I pay a quick visit every day some blogs and information sites to read articles,
but this weblog provides quality based articles.

22. I do not even know how I ended up here, but I thought this
post was good. I don’t know who you are but certainly you are going to a famous blogger if you

23. Very good post. I will be facing many of these issues as well..

24. Fantastic goods from you, man. I have understand your stuff previous to and
you are just too excellent. I actually like what you
have acquired here, certainly like what you are saying and the
way in which you say it. You make it entertaining and you still take care of
to keep it sensible. I can’t wait to read far more from you.
This is really a tremendous website.

25. It’s really a nice and useful piece of info. I’m glad that you shared this useful info with
us. Please keep us up to date like this. Thanks for
sharing.

26. Do you have a spam problem on this website; I also am a
blogger, and I was curious about your situation; we have created some
nice procedures and we are looking to exchange solutions with
other folks, be sure to shoot me an e-mail if interested.

27. I think that everything said made a great deal of
solid, however suppose you added a title that grabbed a person’s
attention? I mean Vectors, Scalars, and Unit-less Values, Part 1 | Rigging Lab
Academy is kinda plain. You might glance at Yahoo’s front page and note
how they write post titles to get people to open the links.
You might add a video or a picture or two to get readers excited about everything’ve written. Just
my opinion, it might bring your posts a little bit more interesting.

28. Good day I am so grateful I found your weblog, I really found you by mistake, while I was searching on Askjeeve for something else, Anyways
I am here now and would just like to say thank you
for a incredible post and a all round entertaining blog (I also love the theme/design),
I don’t have time to go through it all at the minute but
I have book-marked it and also included your RSS feeds, so when I have time I will be back to read much more,
Please do keep up the superb job.

29. Hello there! I know this is kinda off topic nevertheless I’d
figured I’d ask. Would you be interested in exchanging links or maybe guest authoring a blog post or vice-versa?
My site goes over a lot of the same subjects as yours and I believe we could greatly benefit from each other.
If you’re interested feel free to send me an e-mail.
I look forward to hearing from you! Superb blog by the way!

30. I’m extremely impressed with your writing skills and also with the layout on your blog.
Is this a paid theme or did you customize it yourself?
Either way keep up the nice quality writing, it’s rare to see a great blog
like this one these days.

31. Thank you for the good writeup. It in fact was a amusement account it.

By the way, how could we communicate?

32. Heya are using WordPress for your blog platform? I’m new to
the blog world but I’m trying to get started and set up my own. Do you need any html coding expertise to
make your own blog? Any help would be greatly appreciated!

33. Hello very cool web site!! Guy .. Beautiful .. Wonderful ..

I’ll bookmark your website and take the feeds also? I am happy
to find a lot of useful information here within the post, we want
develop extra strategies on this regard, thank you for sharing.
. . . . .

34. Thank you for the good writeup. It in reality was once a enjoyment
account it. Look complicated to more added
agreeable from you! However, how could we communicate?