Spamming your flist
Jan. 27th, 2009 03:21 pm![[personal profile]](https://www.dreamwidth.org/img/silk/identity/user.png){kind=small}
chargirlgeniusOk, so I'm home, and blissfully stuck here. I'm posting a lot. Sue me. ;-)
My Latin plea reminds me that I never followed up on my physics plea a while ago. The gist of it was that I was asking for an easy way to explain why pulling on a rope sideways exerts more force on the end of the rope than pulling on it directly.
I needed to explain why lacing rings sometimes gap more than using eyelets. Here's what I ended up with (In the Eyelets and Lacing article here):
Why [do lacing rings tend to gape more often]? The forces pulling at the opening of a fitted dress are largely horizontal. The body is trying to pull the dress open horizontally, but the lace is holding it closed. If your lace is more horizontally situated, it’s going to be more effective at countering the horizontal force of the dress pulling open. If the lace is vertical, it’s almost completely perpendicular to the horizontal force, and much less effective. Why? Well, it has to do with physics, trigonometry, and a principal known as vector addition4. In other words, that’s just the way it works. A dress made with lacing rings is much more likely to gape at the opening.
4:There’s a common problem given to high school physics students which illustrates the principal. If your car is stuck in the mud, there’s s telephone pole directly in front of it, and you have a very strong rope or chain, what do you do? The answer is to tie the rope to the car and to the pole, then push or pull on the side of the rope. The horizontal pull is going to translate into a much stronger force being applied to the front of the car to move forward (vertically) than it would if you were to directly pull on the rope.
It wasn't highly scientific, but with the info that you all shared, it helped me frame my thoughts in a way that I could explain. At least, I *hope* it came out ok. :-D Thank you.
ETA: Ack! Just saw a typo in my PDF. I should really go clean those up.
My Latin plea reminds me that I never followed up on my physics plea a while ago. The gist of it was that I was asking for an easy way to explain why pulling on a rope sideways exerts more force on the end of the rope than pulling on it directly.
I needed to explain why lacing rings sometimes gap more than using eyelets. Here's what I ended up with (In the Eyelets and Lacing article here):
Why [do lacing rings tend to gape more often]? The forces pulling at the opening of a fitted dress are largely horizontal. The body is trying to pull the dress open horizontally, but the lace is holding it closed. If your lace is more horizontally situated, it’s going to be more effective at countering the horizontal force of the dress pulling open. If the lace is vertical, it’s almost completely perpendicular to the horizontal force, and much less effective. Why? Well, it has to do with physics, trigonometry, and a principal known as vector addition4. In other words, that’s just the way it works. A dress made with lacing rings is much more likely to gape at the opening.
4:There’s a common problem given to high school physics students which illustrates the principal. If your car is stuck in the mud, there’s s telephone pole directly in front of it, and you have a very strong rope or chain, what do you do? The answer is to tie the rope to the car and to the pole, then push or pull on the side of the rope. The horizontal pull is going to translate into a much stronger force being applied to the front of the car to move forward (vertically) than it would if you were to directly pull on the rope.
It wasn't highly scientific, but with the info that you all shared, it helped me frame my thoughts in a way that I could explain. At least, I *hope* it came out ok. :-D Thank you.
ETA: Ack! Just saw a typo in my PDF. I should really go clean those up.