this post was submitted on 18 Jan 2024
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xkcd

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For decades I've been working off the accumulated rotation from one long afternoon on a merry-go-round when I was eight.

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[–] [email protected] 57 points 9 months ago (2 children)

Don't show this to anyone with OCD.

[–] [email protected] 11 points 9 months ago* (last edited 9 months ago) (1 children)

Have OCD, occasionally counterspin to reverse one I've done but only single spins. This would drive me crazy lol

Also related: https://www.xkcd.com/2679/

[–] [email protected] 2 points 9 months ago

holy shit i do this string thing and i get stressed if i get too many winds around a place i don’t like

[–] [email protected] 10 points 9 months ago (1 children)

I don't have OCD but I definitely have this spinning thing. The worst thing is when you're unsure if you are short a spin or not, it's like having a sneeze stuck that won't come out

[–] [email protected] 13 points 9 months ago

And you're certain you don't have OCD...?

[–] [email protected] 46 points 9 months ago (1 children)

We should all start spinning counterclockwise in the north and clockwise in the south to affect the planet's rotation and create a massive westward tidal wave that will finally take care of Florida.

[–] [email protected] 20 points 9 months ago (1 children)

Florida will take care of its self with how things are going.

[–] [email protected] 13 points 9 months ago

It’s so adorable when they grow up and can take care of themselves

[–] [email protected] 16 points 9 months ago

Fuck, I thought I was the only one.

[–] [email protected] 14 points 9 months ago* (last edited 9 months ago) (1 children)

Ultimatelly it depends on the distribution of the Human population all over the World.

It's fine to not to offset your rotations at the end of the day if there are people on the other side of the World in average rotating about the same as you do and who thus offset you rotations with their own.

Also if some people around you tend to accumulate clockwise rotations and others counter-clockwise ones, it's all fine as you're offsetting each other and ditto if your personal accumulation of rotation for each day has an equal chance to being clockwise as it has of being counter-clockwise since you're offsetting yourself over time (granted, if not in the equator you've made days a little longer or a little shorter in between, but all in all it's fine).

[–] [email protected] 10 points 9 months ago

New reason for us to have a keep-left policy on our roads while yanks have a keep-right policy on theirs....

[–] [email protected] 9 points 9 months ago

That's why you should only go to those larger merry-go-rounds where everything rotates in one direction and your immediate region rotates on the other.

[–] [email protected] 9 points 9 months ago (1 children)
[–] [email protected] 2 points 9 months ago (1 children)

explainexplainxkcd exists?

[–] [email protected] 8 points 9 months ago (3 children)

This guy: keeps records and spends extra time.

Me: Goes back home.

[–] [email protected] 6 points 9 months ago (1 children)

Just have to be sure to use the same doors so the string/worldline doesn't get caught.

[–] [email protected] 2 points 9 months ago

Yeah, but if you get spun around inside a room you still have problems

[–] [email protected] 3 points 9 months ago (1 children)

Three rights make a left. It's entirely possible to have an unbalanced ratio of left to right rotations in a day

[–] [email protected] 10 points 9 months ago

Triangular grid guy: "Guess I'm going back the way I came."

Hexagonal grid guy: "What is left. What is right. This did nothing! Nothing!"

Guy on Penrose tiling: "Get me out of here!"

(In before: "You have the first two the wrong way around." Not if they're walking the edges.)

[–] [email protected] 3 points 9 months ago

If you are doing that by car, then the cloverleaf will add to your spin, not cancel it out.

[–] [email protected] 6 points 9 months ago

Saturated reaction wheels are a big problem

[–] [email protected] 5 points 9 months ago* (last edited 9 months ago) (1 children)

If every human on the planet just started running in the same direction, could we collectively affect the rotation of the planet like running on a ball? 🤔

[–] [email protected] 14 points 9 months ago (1 children)

Yes, we would affect the Earth's rotation. It's just by a ridiculously small amount that nobody would ever be able to measure.

[–] [email protected] 5 points 9 months ago* (last edited 9 months ago) (4 children)

Now I am wondering how many humans would it take to be measurable and significant?

[–] [email protected] 5 points 9 months ago* (last edited 9 months ago)

The mass of the Earth is 5.972 × 10^24^, so you would need 5.972 × 10^20^ humans of 100 Kg each all turning in the same direction to make the Earth rotate 1% the other way (so about 597,200,000 trillion humans).

PS: I might be slightly wrong here as rotations have to do with angular momentum which is a bit more complicated than the linear kind because rotational inertia doesn't depende on mass alone, but the law of conservation of angular momentum does apply.

[–] [email protected] 3 points 9 months ago

how fast do you spin them?

[–] [email protected] 1 points 9 months ago (1 children)

Whatever amount of people it'd take, the effect we'd make, would cancel at break.

[–] [email protected] 1 points 9 months ago (1 children)

I was going to say a similar thing, how are you going to get gone without canceling it out.

But also if you walked away from the equator then walked until you were directly north/ south of your home before walking home, some effect would remain.

[–] [email protected] 1 points 9 months ago (1 children)

I don't believe that to be correct, but I'm to stupid to refute you. So I'll take it as facts. Thank you for enlightening me.

[–] [email protected] 1 points 9 months ago

It's because your return journey is closer to the axis of the earth so your action has less torque.

[–] [email protected] 1 points 9 months ago