English Language & Usage: Multi-Layered Discourse Room

Cerberus

17:08

@MattE.Эллен Right, I will keep it in mind.

So do you need metal to be a in lattice in order to divert solar winds?

Or will any (dispersed) clump of metal atoms do?

Færd

17:23

In order to be safe from which, the particles or their radiation?

Cerberus

In order to prevent the winds from blowing away the atmosphaere of Mars.

Færd

Oh.

I didn't read the previous messages.

Cerberus

Don't worry.

Færd

worries not

Cerberus

good

Mitch

17:28

@Cerberus you can divert solar winds in many ways.

one of them is by having a magnetic field.

I think there is only one way to have a magnetic field and that is by having a concentratino of iron, either as a ball in the center, or as a spherical shell near the surface. as long as it is spinning (if it's not spinning you don't get the field).

Cerberus

You can use electricity to generate the field as well.

Færd

You don't get a magnetic field just by spinning metal.

Matt E. Эллен

use the solar wind to power solar wind turbines to generate electricity to power an electromegnetosphere to divert the solar wind... flawless

Cerberus

Good idea.

I like its circularity.

Matt E. Эллен

circles are the best shape

Færd

17:35

@Cerberus You'll need a varying electric field for that.

The variation needs a power source, and I don't think using the solar wind itself would do.

But I don't intend to get technical on Matt's charming theory.

Matt E. Эллен

lol

Cerberus

2 hours ago, by Cerberus

But you need either a googol of metal, or a googol of energy...?

Færd

Depends on the power of the winds. I'd have to look that up, but I'm not in the moon.

Oops, mood.

Matt E. Эллен

it would be easier to measure on the moon, as there's no atmosphere :D

Færd

Right. What I meant.

Matt E. Эллен

17:44

classic "the keys are right next to each other": english.stackexchange.com/posts/382333/revisions

(meme I'm referencing)

Færd

Funny meme.

Speaking of the moon, maybe we should try the atmosphere thing on the moon first, before going all the way out to Mars.

We'd need some heavy gases though.

Matt E. Эллен

there aren't many heavy gases

make a lead aerosol perhaps

Færd

There is one called Human Fart.

Matt E. Эллен

I suppose mercury would be easier

@Færd we can't unleash that on an unsuspecting universe

Færd

Yeah, would be a great waste.

Matt E. Эллен

17:54

plus, nothing is funnier than a fart noise

Færd

People must wear earplugs in the toilet.

The laughter makes a vicious circle.

Mitch

you still need a strong enough gravity to keep the gas in

@Færd I don't hink you're using the toilet right then

Matt E. Эллен

> english - the php of spoken languages

Færd

@Mitch The main factor is the escape velocity, which depends on the heaviness of the particles and the temperature.

@Mitch I prefer the British toilet to the American bathroom.

Mitch

krypton then?

Færd

18:04

Maybe. The calculation wouldn't be hard.

Correction: the escape velocity does not depend on the temperature. The average velocity of the particles does.

Mitch

@Færd isn't average velocity of particles the same as temperature?

Færd

The average of the squares is.

I.e, the average kinetic energy (in an ideal gas).

Except for some coefficients.

Mitch

Terraforming of Mars

Terraforming of Mars is a process by which the surface and climate of Mars would be deliberately changed to make large areas of the environment hospitable to humans, thus making the colonization of Mars safer and sustainable (see Planetary engineering). There are a few proposed terraforming concepts, some of which present prohibitive economic and natural resource costs, and others that may be achievable with foreseeable technology. == Motivation and ethics == Future population growth, demand for resources, and an alternate solution to the Doomsday argument may require human colonization of bodies...

a 1 Tesla strength magnetic field placed at L1 point would deflect the solar wind enough (don't need a planet enveloping field like Earth's (though that would help with limiting radiation too))

Færd

Oh, nice. I wonder how much it will take for Mars to restore some decent atmosphere.

Maybe not too much for simple unicellular organisms.

Mitch

18:22

but current MRI machines at your local emergency room have low energy options at 1.5T.

so energy level extremely feasible

except the solar wind is not powerful enough to drive that. maybe solar panels? I don't know.

Færd

Drive what?

Matt E. Эллен

@Mitch what would the volume of the field need to be?

Færd

18:49

Drive the satellite, I suppose.

@MattE.Эллен Do you mean the spatial size of the magnet?

Matt E. Эллен

@Færd yes

Færd

From afar, large magnets and small magnets look the same. The size is not much of a factor in their strength.

Matt E. Эллен

given that a magnetic field's strength is related in (I think) an inverse cube law to the distance from it

or maybe an inverse square

Færd

So, I think Mitch is saying that having a 1 Tesla field at a single point will provide the field we want.

Matt E. Эллен

so the size of the magnet is important as it will determine the reach of the field

Færd

18:58

@MattE.Эллен That.

Mmm...

@MattE.Эллен If you have a 1 Tesla field at point A, then you'll have an approximately 1 Tesla field at any point near A.

It will take some time for me to figure out how to explain this.

Matt E. Эллен

given that I've worked with 1 tesla magnets, I can tell you that "near" isn't very far at all

skull petrol

Aha! that explains your magnetism :D

Færd

@MattE.Эллен OK. You have a 1 Tesla field at point A. The strength of the filed decreases according to the inverse square of your distance from A, right?

Matt E. Эллен

yes

Færd

With that formula the strength of the field can be calculated at any point.

The size of the magnet doesn't exist in that formula.

A good question would be "Why?".

M.A.R.

19:08

Why?

Matt E. Эллен

but how close you are to A is related to the size of the magnet

Færd

@M.A.R. We'd have to know some things about what happens in a magnet and how it prduces a magnetic field.

@MattE.Эллен Would you explain that? I don't understand it.

Matt E. Эллен

@Færd if you have a magnet shaped like a coin then the field is a different shape to one shaped like a sphere, correct?

Færd

Yes.

But not from afar.

When you get far enough for those two to look like two dots, their magnetic field will look much the same too.

Matt E. Эллен

ok

Færd

19:25

@M.A.R. I gave a bad answer to your question. Another answer is that you can determine the velocity with which you throw a rock, but once you threw it, you can't affect its velocity anymore. Analogous to that, a magnet can produce a magnetic field, but cannot determine in what way it distributes in space.

Matt's point was something else though.

Færd

20:01

I did a terrible job explaining things tonight. Better take my leave.

skull petrol

20:16

Cya

Tonepoet

20:46

@SBM Are you sure about that?

Wilson

Anyone have any insight into the word invert? Pipe invert and obvert: Why is it called invert?

Would people get upset if I posted this kind of thing on the English Language SE?

Tonepoet

@Wilson It appears to be because it's an upsidedown arch.

I don't know about obvert though

Wilson

Well, I think this definition could be the perfect fit: 4. To divert; to turn into another channel; to embezzle. [Not in use.]

The invert measurement is taken where the pipe meets the manhole.

Tonepoet

@Wilson I doubt that because it's used on a diagram describing the shape of a pipe.

Wilson

@Tonepoet In civil engineering, the word invert is often used to describe the interior, bottom elevation where the pipe meets the manhole. This is essentially a diversion, turning water into another channel.

Tonepoet

20:56

@Wilson Crossposting isn't allowed, so you'd have to delete the original question first, and the people on Engineering would have more experience with pipes specifically than us. However with that having been said, you provided some research which is a good start. The only problem I can think of is if people think it's unclear. I don't think it is, but the others might not agree if you don't explain why the most likely entries are doubtful.

@Wilson That makes some sense, but this explanation doesn't explain anything about the use of obvert in opposition to invert.

Wilson

@Tonepoet Yeah, I guess you're right. I can't just ignore obvert.

Tonepoet

21:14

@Wilson The Century Dictionary and Cyclopedia is a little more helpful than Webster's perhaps: Invert "In arch., An inverted arch; specifically the floor of a lock-chamber of a canal, which is usually in the form of an inverted arch, or the bottom of a sewer. 'The bottom of the sewer is called the invert from a general resemblance in construction to an "inverted" arch.' Mayhew, London Labour and London Poor, II 445."

I probably should have thought of the C.D.C. first, because it, like its predecessor The Imperial Dictionary, wished to build upon the technical use of language over Webster's, and it's one of the largest dictionaries in the English Language, albeit somewhat of an antique.

Wilson

0

Q: Pipe invert and obvert: Why is it called invert?

In civil engineering, the words invert and obvert are used in the context of pipe elevations. I gather that invert means: interior bottom elevation of pipe, and obvert means: interior top elevation of pipe. However, using the word invert in this context seems strange to me. To me, none of thes...

I modified it slightly, and posted it on the English SE.

In terms of cross-posting, this question gives some clarity: Draw attention to a question in a different SE community?

'Ask your question on the target site as well. This can be OK , so long as you customize your question for the target audience (i.e. not copy-paste).'

Tonepoet

@Wilson I'm judging by this post

Wilson

@Tonepoet Thanks for your points from the C.D.C.. Very interesting.

Tonepoet

21:31

@Wilson I think its the votes on the answers which probably count for more than comments in terms of getting policy off of meta, though on the other hand Jeff was the leader of the website and I'd assume it'd take somebody else with equal standing to rescind his edicts during that time. If so, perhaps the main question is if this is different enough. I'm not really sure.

@Wilson You're welcome to it.

Wilson

21:53

@Tonepoet Ok, I made an answer out of the CDC definition you found: english.stackexchange.com/a/382396/201801

Tonepoet

@Wilson I'll wait to see what the moderators do with the question.

@Wilson You don't need to accredit me. Just paste this into your answer:

>*[The Century Dictionary and Cyclopedia](http://www.micmap.org/dicfro/search/century-dictionary/invert)* s.v. [Invert](http://www.finedictionary.com/invert.html): In architecture, an inverted arch; specifically, the floor of the lock-chamber of a canal, which is usually in the form of an inverted arch, or the bottom of a sewer.
>>The bottom of the sewer is called the invert from a general resemblance in construction to an "inverted" arch. *Mayhew, London Labour and London Poor*, II 445.

Or rather, the links are truncated...

So if you'd allow me to do it that'd probably be better.

Wilson

@Tonepoet I'll delete the credit. You could always just suggest an edit.

Tonepoet

My edits get forced through because I have over 2000 rep.

But if you're fine with me editing it...

Wilson

Yes. Sure. Have at it.

Tonepoet

@Wilson, I'm done.

Wilson

22:08

@Tonepoet It looks a lot better. Thanks. Now, it's pub-time. Cheers.

Tonepoet

@Wilson Okay; bye bye.

@wilson Uhm, I did the links in that order because Finedictionary has more dictionaries listed on it than just The C.D.C. It also has Webster's Revised Unabridged Dictionary, Chambers' 20th century Dictionary and Wordnet.

I guess Dicfro does too, although they require you to use dropdown menus to see that.

Wilson

22:28

@Tonepoet Ok. I'll put it back.

Tonepoet

@Wilson Either way is fine really. I'm just saying why I did it that way.

Wilson

I see now... I had only hovered over the links to check that they pointed to the right spot. I should have looked closer. My stupid.

Transcript for

English Language & Usage: Multi-Layer…