Tallinn?
Even better than a cart of apples
Submitted 1 year ago by HootinNHollerin@lemmy.world to science_memes@mander.xyz
https://lemmy.world/pictrs/image/70b9eea8-4821-4c8a-8eb8-21b1c50199cf.jpeg
Comments
pewgar_seemsimandroid@lemmy.blahaj.zone 1 year ago
toynbee@lemmy.world 1 year ago
When I was young, my mother showed me an educational book that had things like riddles, puzzles, and mental exercises in it. One of these entries had a short, mundane paragraph, followed by some form of “what was wrong with that text?”
It then explained that I had missed the word “the” being on the end of one line but also the start of the next line which, indeed, I did miss. It suggested that the human mind couldn’t see duplicate words split in such a way, at least in English, unless actively looking for them.
I now know that, while it did trick me, its theory was incorrect … Because I can’t not see “from from.”
Wirlocke@lemmy.blahaj.zone 1 year ago
Maybe you built up antibodies cause I didn’t notice at all.
ILikeBoobies@lemmy.ca 1 year ago
That that
Had had
Are proper English
Then there’s this …wikipedia.org/…/Buffalo_buffalo_Buffalo_buffalo_…
muntedcrocodile@lemm.ee 1 year ago
Its almost like we arw tought these things cos they have practical examples.
Liz@midwest.social 1 year ago
Clearly you weren’t paying attention in English.
boonhet@lemm.ee 1 year ago
It has no practical use cases.
Scolding7300@lemmy.world 1 year ago
He sin
muntedcrocodile@lemm.ee 1 year ago
I was always better at maths. And dr gpt has solved the english issue.
Anticorp@lemmy.world 1 year ago
Yes, this is why we study physics.
jafffacakelemmy@mander.xyz 1 year ago
Catenary is the magic word here
21Cabbage@lemmynsfw.com 1 year ago
Looks like part of the tension system on a rope tow style ski lift.
dragonfucker@lemmy.nz 1 year ago
Drag believes this is from an electric railway. The pulleys and weights keep the cable taut so the train can stay connected to it at high speeds.
perviouslyiner@lemmy.world 1 year ago
And the weights are like a bigger version of the weight-hangers from science classes.
Iheartcheese@lemmy.world 1 year ago
What’s it pull?
Iron_Lynx@lemmy.world 1 year ago
In case people don’t want to click a link, let me explain it here:
If you want to use overhead line electrification, you need to suspend a wire over the rails. In theory, you could simply hang up a wire, but whichever amount of tension you choose, if it’s warmer outside, the wire will droop, potentially causing damage, while if it’s colder outside, the wire will pull taut and may snap. So you want a system to account for external temperature.
Instead of picking a tension at a standard installation temperature, you pick an amount of desired tension and use weights to pull it taut. Now, if the wire heats up and extends, the weights drop, and if the wire cools down and contracts, the weights are pulled up.
And to keep the amount of weight you need to add under control, you use a series of pulleys to control the tension in the wire.
In NL, the mainline system looks a lot simpler: They have only one wheel, but that’s two pulleys: a larger one and a smaller one. The larger one holds the weight, while the smaller one holds the wires.
Iron_Lynx@lemmy.world 1 year ago
With the previous ELI12 under control, let’s ELI>12 overhead line catenary a little more. For instance, why do you need tension in the first place?
Fact of the matter is that using a rigid conductor is problematic with high voltage AC (skin effect and such), plus it’s more visually intrusive than wires. Meanwhile, a wire will sag, regardless of how much tension you can practically apply. So you need a few devices to help keep the wire at height.
For one, the wire is supported every few dozen metres. Secondly, there’s a second wire strung above the first one. And while both wires are pulled taut, there are dropper wires between the upper and lower wires, which vary in length. Longer near the poles, while at the shortest near the middle between two poles, which creates a structure similar to a suspension bridge to keep the contact wire within a tight margin of vertical space.
IndustryStandard@lemmy.world 1 year ago
The train duh
LegoBrickOnFire@lemmy.world 1 year ago
Those are things that regulate the tension in the overhead cables in train tracks. With the variation of temperature cables tend to contract/expand and this systems allows the cables to do so freely with a constant tension provided by the weights.
verstra@programming.dev 1 year ago
These are so simple and yet so clever. When i noticed them the first time i started noticing them everywhere (on all rail infrastructure).
spankmonkey@lemmy.world 1 year ago
FROM
FROM
Martineski@lemmy.dbzer0.com 1 year ago
Yeah, memes following the format with top and bottom text very often have repeating word as a joke.
expatriado@lemmy.world 1 year ago
double pulley, for added complexity
plactagonic@sopuli.xyz 1 year ago
My brother started working for company that makes these things and now he points every little detail on them.
“Look at this insulator” “Look these anchor points are made at factory I visited last week” …
DogWater@lemmy.world 1 year ago
He does important work to keep railroads working I imagine then! I believe those are the tensioners for high voltage lines over trans and railways
plactagonic@sopuli.xyz 1 year ago
Lol, mainly documentation and cad work. Dealing with architects if it is for trams or trolleybus lines, politicians and bureaucrats that makes the public orders and stuff like that.
pageflight@lemmy.world 1 year ago
I would subscribe to his YouTube channel!
JackbyDev@programming.dev 1 year ago
Isn’t this a tensioning device for an electric train?