Home Β» Forum Β» Editors/Reviewers Hangout

Forum: Editors/Reviewers Hangout

The momentum of inertia

Zom 🚫

Every so often I come across what I think is a newly increasing use of an incorrect word. One such is 'inertia'.

As an example, in a story I have been recently re-reading I came across, "I learned that force equals mass times inertia." It is just the most recent of the many times I have seen 'inertia' used where 'momentum' or 'velocity' should be used.

Going back to my high school Newtonian physics, and paraphrasing badly: 'inertia' is the tendency to stay as you are, and 'momentum' is the tendency to keep going as you are. Force is required to change either. 'Velocity' is just vectored speed, and has little to do with 'inertia'.

I have tended to give these uses of 'inertia' the 'oh dear' response and move on, but my innate sense of caution has finally lead me to ask, "is there something going on here that I don't understand?"

Is there some reason, other than ignorance, that folk are using 'inertia' in a way that seems entirely inappropriate? Has some US state legislated a change in the naming of SI units? What is going on?

Vincent Berg 🚫
Updated:

@Zom

Is there some reason, other than ignorance, that folk are using 'inertia' in a way that seems entirely inappropriate? Has some US state legislated a change in the naming of SI units? What is going on?

I'd largely chalk it up to either ignorance or simple dunder-headedness (i.e. they realize the difference, but were typing too fast to notice)β€”largely based on whether they've written much science fiction in the past.

However, I would drop them a note, each time, just to alert them to a simple-to-fix error. Tossing in a quick dictionary definition or a link to a Google 'inertia vs momentum vs velocity' link won't hurt, either.

Replies:   Not_a_ID  Zom
Not_a_ID 🚫

@Vincent Berg

I'd largely chalk it up to either ignorance or simple dunder-headedness (i.e. they realize the difference, but were typing too fast to notice)β€”largely based on whether they've written much science fiction in the past.

And then it transpired that the physicist threw a fit upon hearing someone speak about centrifugal force. "It is centrepital force, you oaf!"

"And transpiration is how plants breath" added the biologist.

Replies:   Zom
Zom 🚫
Updated:

@Not_a_ID

Hmmm, breathy plants :-) It's good to see a frugal by pital. It's like the innie and outie force pair, yes?

Replies:   Vincent Berg
Vincent Berg 🚫

@Zom

Hmmm, breathy plants :-)

That's why everyone appreciates the minty freshness of Certs, plants and animals alike! 'D

Zom 🚫

@Vincent Berg

Thanks CW. It's happening a lot lately, and sometimes by authors that I expect would know better. I try not to be a grammar Nazi at large, but will consider your advice.

Replies:   Grant  Vincent Berg
Grant 🚫

@Zom

I try not to be a grammar Nazi

This isn't about Grammar, it's about facts.

There have been one or 2 stories that were meant to be Science fiction, but some of what was written was just so wrong I bailed out.

Replies:   Zom  Vincent Berg
Zom 🚫
Updated:

@Grant

it's about facts

You want facts to get in the way of fiction?

Seriously, the only reason it flags for me at all is that this is the way words unintentionally change meanings.

The language is fluid, well viscous actually, and does change, but hijacking words and phrases through ignorance and forcing meaning changes on them by sheer weight of numbers is not a reasonable method, IMHO.

Take 'terrific' as an example. It originally, and still does, mean something terrifying. But now it is mostly used to describe something wonderful and exciting, like Taylor Swift, or maybe that is using the original meaning.

It can get really confusing for literalists ...

Replies:   Vincent Berg  Grant
Vincent Berg 🚫
Updated:

@Zom

Damn! I hate how mismatching tags cause multiple paragraphs of a response to be erased!

Take 'terrific' as an example. It originally, and still does, mean something terrifying. But now it is mostly used to describe something wonderful and exciting, like Taylor Swift, or maybe that is using the original meaning.

Your post made me curious, so I did some online research. "Terrific" didn't come from "terror", although both came from the Indo-European base ters-/tres- meaning "to shake". You can shake with both fear and excitement, without one excluding the other.

Check out the Grammarphobia blog: How "terror" gave us "terrific".

Both terror and terrific come from the Indo-European base ters-/tres- meaning "to shake". You can shake with excitement as easily as you can shake with fear without the one taking away from the other.

"terrific" originally did mean "terrifying", but later transitioned into "of great size or intensity" and eventually into "impressive" or "splendid" (whether positive or negative).

This is an example of amelioration or pejoration, where works eventually take on additional usages. For example, "pretty" originally meant cunning or craft in Old English, and only came to be "attractive" in the 1400s. Similarly, "crafty" originally meant "clever", and only changed to mean "cunning" until the late 1300s.

If your definition of 'acceptable English' doesn't include words coined in the 1300s, then you'll have to abandon 95% of the English spoken today. Hell, many of the words Shakespeare used were purely invented by him, with no recorded uses before he created them. Does that mean you'll now reject Shakespeare as a modern "upstart"?

Replies:   Zom
Zom 🚫
Updated:

@Vincent Berg

"Terrific" didn't come from "terror"

It's not coining I object to, rather hijacking. Sure there has been lots of it, and it is ongoing, but I don't have to support it, just like I don't support piracy ;-)

A reference I found shows:

mid 17th century: from Latin terrificus, from terrere 'frighten'

Also see:

http://www.dictionary.com/browse/terrific

and:

https://www.merriam-webster.com/dictionary/terrific

Sadly both of them, and I suspect may others, have relegated the original meaning to #3. Sigh ... I curse semantic amelioration :-(

Replies:   Vincent Berg
Vincent Berg 🚫

@Zom

Try searching "terrific etymology". You'll get much more detail than checking dictionary definitions.

Replies:   Zom
Zom 🚫
Updated:

@Vincent Berg

Try searching "terrific etymology"

I try to stick to authoritative sources, as much as that is possible on the Internet. Known dictionary sources tend to be correct, albeit a bit terse. I do have a hard dictionary, but it was printed in 1964 :-)

ETA: Interestingly, in that dictionary the primary definition for 'terrific' is "causing great terror". So it's all changed since 1964. Sigh ...

Replies:   Vincent Berg
Vincent Berg 🚫
Updated:

@Zom

> try Goggling "terrific etymology"

I try to stick to authoritative sources, as much as that is possible on the Internet. Known dictionary sources tend to be correct, albeit a bit terse. I do have a hard dictionary, but it was printed in 1964 :-)

No, you're clearly wrong in this case. Dictionaries will only list, at MOST, a singe sentence etymology, which often doesn't accurately describe how the word evolved. Often it simply consists of (ex: "derived from a Latin room in 18xx").

You can't get 'factual' etymological definitions from a Dictionary! They simply don't allocate enough room for the full history.

Grant 🚫

@Zom

You want facts to get in the way of fiction?

No, I want them to support fiction.

Seriously, the only reason it flags for me at all is that this is the way words unintentionally change meanings.

To me it shows ignorance.

In general language words may change their meaning over time.
These are terms that relate at a basic level to our universe. Unless the very nature of our universe changes, then those words meanings/definitions will not change.

Dominions Son 🚫

@Grant

Unless the very nature of our universe changes, then those words meanings/definitions will not change.

What nonsense. Just because the basic forces of the universe don't change, doesn't mean that the words to describe them won't change.

Replies:   Grant  Vincent Berg
Grant 🚫

@Dominions Son

What nonsense. Just because the basic forces of the universe don't change, doesn't mean that the words to describe them won't change.

I guess this needs repeating In general language words may change their meaning over time.

Different languages use different words.
But the present words that are used to describe various forces haven't changed since those forces were discovered/described. The only way for those words to change would be through misuse (ie general language) or for the nature of the universe itself to change. Rather unlikely.

It could be that yet another system could be developed to replace the metric system, which replaced (for most of the world) the earlier imperial system.
Even so, the old words from the earlier systems would still have the same meanings & relationships as they do now.

Replies:   Zom
Zom 🚫
Updated:

@Grant

through misuse

It seems though that enough misuse redefines the use. I can't help thinking that 'inertia' will begin to become the de-facto word for those techy physics movement thingies. It's shorter than 'momentum' and 'velocity' and all those other big words, and you hear it lots on the news in financial reports.

Replies:   Vincent Berg
Vincent Berg 🚫
Updated:

@Zom

It's shorter than 'momentum' and 'velocity' and all those other big words, and you hear it lots on the news in financial reports.

Geez! You've got to give this agenda a break. Although "momentum" wasn't originally intended as a financial term, they're using the word properly in the case you're quoting. A trend has "momentum" because the movement is consistent (i.e. it doesn't change, or speed up and slow down, instead it continues as it has). An example of this, which might irk experiment scientists but still be proper, is if a particular stock jumped all over the place, but then settled into a steady trend. You could legitimately say the stock now has "momentum", meaning that it's just become stable and consistent.

Using an existing word in a new context is not 'bastardizing' a word, it's merely 'borrowing' a word from one context to use in another (just like we 'borrow' words from other languages when our language has NO appropriate words for something).

In short, it's time you get off your damn high horse. I'm NOT saying that you don't have a point, but you're carrying your argument to extremes!

Note: please excuse me for dumping on you here, as I'm expressing my frustration over your repeating the same thread as Grant has. Thus I'm complaining about the 'proverbial' "you", rather than what you specifically said.

Replies:   Zom
Zom 🚫

@Vincent Berg

Although "momentum" wasn't originally intended as a financial term

If you read the sentence carefully, you will see it was 'inertia' I was referring to, not 'momentum' which was just a contrast example.

Besides, I want to have the last word (pout pout).

Dominions Son 🚫

@Zom

Besides, I want to have the last word

Tough.

Replies:   Zom
Zom 🚫

@Dominions Son

Tough.

That's the idea! I have some inertia when it comes to getting a thread back on topic, even though there is a concerted effort to fork it onto feedback to authors :-)

Replies:   Dominions Son
Dominions Son 🚫

@Zom

You want the last word, here it is: zyzzogeton

http://www.alphadictionary.com/goodword/word/zyzzyva

:P

Replies:   Zom  Ross at Play
Zom 🚫

@Dominions Son

here it is: zyzzogeton

And yet, what you point me to is about 'zyzzyva'. Great word though. But not your standard English dictionary class of publication. No offence to the Heritage types. I wonder if there is a 'Dictionary of Apnoea Terms' which would doubtless include 'Zzzzzzz', defined as the noise a throat makes when overcoming breathing INERTIA :-)

Dominions Son 🚫

@Zom

And yet, what you point me to is about 'zyzzyva'.

You missed this from the cited link

The last word in the Merriam-Webster Unabridged is a related word, zyzzogeton "a genus of large South American leafhoppers of the family Cicadellidae"

Replies:   Zom
Zom 🚫

@Dominions Son

You missed this from the cited link

Why would you say that?

sejintenej 🚫

@Zom

And yet, what you point me to is about 'zyzzyva'. Great word though. But not your standard English dictionary class of publication

Very important insect in South America. Definitely a great word and in my American/Canadian dictionary. (The Canadian lexicographer is/was a professor in Chicago)

Replies:   Vincent Berg
Vincent Berg 🚫

@sejintenej

And yet, what you point me to is about 'zyzzyva'. Great word though. But not your standard English dictionary class of publication

Very important insect in South America.

Is there a corresponding abaabdz bug?

Ross at Play 🚫

@Dominions Son

You want the last word, here it is: zyzzogeton
http://www.alphadictionary.com/goodword/word/zyzzyva

I'm feeling very sleepy. Time for a zzz. :)

Vincent Berg 🚫

@Zom

If you read the sentence carefully, you will see it was 'inertia' I was referring to, not 'momentum' which was just a contrast example.

@Dominions Son

Tough.

The same applies to 'inertia' (assuming they use it correctly). If a stock suffers from inertia, it won't change direction, thus a losing stock will continue under-performing. The concepts apply to different subjects, but often, the definitions shift to better fit each usage.

That's not a bastardization of the language, since the original definition still applies, instead it's creating room for new, more precise uses in different contexts.

Replies:   Zom
Zom 🚫

@Vincent Berg

That's not a bastardization of the language

I didn't say it was. I just used it as an example of a much heard word in the public domain. Something to latch on to when wanting a techy word for those movement thingies.

Vincent Berg 🚫

@Dominions Son

What nonsense. Just because the basic forces of the universe don't change, doesn't mean that the words to describe them won't change.

Case in point: as our knowledge of the universe changes, the scientific terms often become more refined, changing over time. That's not 'ignoring what words mean', instead it's using words to reflect situations the original creators of the words never considered.

Vincent Berg 🚫

@Grant

Seriously, the only reason it flags for me at all is that this is the way words unintentionally change meanings.

To me it shows ignorance.

In general language words may change their meaning over time.
These are terms that relate at a basic level to our universe. Unless the very nature of our universe changes, then those words meanings/definitions will not change.

My previous example about the misuse of "theory" is telling here. While it's incorrect to use 'theory' to refer to someone supposition, that's only the technical definition (i.e. for anyone who's not an experimental scientist, "theory" more often mean 'a supposition'). In that case, it's not an invalid usage, it's simply an improper usage (i.e. they're applying a conversations phrase in a scientific discussion, or they're using it conversationally in a story focused on people who should know the difference).

In that case, it's not so much getting facts wrong, as much as it's an improper choice of which definition to apply to a given situation.

And yeah, I realize I'm dicing words, but if you take from the position of the common reader (with little background in conducting experiments or taking Chemistry/Physics classes) the word choices make the most sense.

Vincent Berg 🚫

@Grant

This isn't about Grammar, it's about facts.

Well, I wouldn't say 'facts', as those are observable and repeatable phenomena, whereas word choices are an individual choice, but there are invalid selections, sowing confusion instead of edification.

Note: My choice of "edification" is not a fact, it's simply an appropriate choice. These types of distinctions become very important when you're dealing with the scientific community, which science fiction, by definition, incorporates.

Any time you write science fictions, you have to be mindful and respectful to the scientific process and mindset. Calling a pig an afghan will get you laughed at, yet many writers will mix up precise terms they're not familiar with as if the definitions of words don't matter to the story.

Replies:   richardshagrin  Grant
richardshagrin 🚫

@Vincent Berg

Calling a pig an afghan

A resident of Afghanistan is an Afghan. The vast majority are Muslim and are for religious reasons unwilling to eat pigs, so almost no pigs live in the country. It would be difficult to find a pig there to call an Afghan. On the other hand, calling an Afghan a pig would be an easy way to start a fight.

Replies:   ndogodevushki
ndogodevushki 🚫

@richardshagrin

A resident of Afghanistan is an Afghan.

The problem here is that the first 'a' was not capitalized by the writer, while you capitalized it, changing its meaning. The original use of "afghan" probably refers to a throw or carpet. I have often used an afghan as a blanket of sorts while lying on a couch.

Replies:   Ross at Play
Ross at Play 🚫
Updated:

@ndogodevushki

The problem here is that the first 'a' was not capitalized by the writer, while you capitalized it, changing its meaning. The original use of "afghan" probably refers to a throw or carpet. I have often used an afghan as a blanket of sorts while lying on a couch.

Thank you for the contribution. I haven't noticed you here before, so hello and welcome!

You noted, "the first 'a' was not capitalized by the [original] writer". Looking at who that was, Crumbly Writer, I can almost guarantee you that if he'd proofread what he wrote before posting it he would have noticed the error and changed it to a capital. CW, as we call him, is very busy and he never proofreads his posts here. He usually comes here a few times a day, pounds out some interminably long and mostly, astute comments for our edification, then goes back to his other business. I.E., just learn to ignore his numerous and varied typos.
* *
So, moving on to your point, the question of whether or not the word 'afghan' requires a capital depends on what the writer, at the time, thinks the word is referring to - not necessarily its original meaning. If they use 'Afghan' to mean someone/something from Afghanistan, then they should use a capital because the adjective is referring to a proper noun.

I would not use 'afghan' in English to describe the style of weaving used to make an object. While that would be correct, I think the lesser evil is having readers interpret 'Afghan' as something made in Afghanistan, rather than having almost all of them assume I had made a technical blunder.

Replies:   richardshagrin
richardshagrin 🚫
Updated:

@Ross at Play

afghan

"afghan (blanket)

From Wikipedia, the free encyclopedia

An afghan blanket

Afghans being made for charity by a crochet club.

Afghans being made for charity by US military members at a crochet club.

An afghan is a blanket of knitted or crocheted wool, cotton, linen (or many other kinds of natural materials) or made of any type of man-made material. [1] It is sometimes also called a "throw" of indeterminate size. They are often used as bedspreads, or as a decoration on the back of chairs.[2]

Etymology[edit]

The word afghan refers to the people of the country of Afghanistan. The coverlet was originally produced by the Afghans. The use of afghan in the English language goes back to 1831, when Thomas Carlyle mentioned it in his Sartor Resartus.[3] The first mention of the word referring to the woven rug was in 1877.[4]"

Replies:   Ross at Play
Ross at Play 🚫
Updated:

@richardshagrin

The word afghan refers to the people of the country of Afghanistan.
- quoted from Wikipedia

I spit on that one.

If the word "refers to the country of Afghanistan" then it is incorrect to not write it with a capital.

Ngrams agrees with me! This query shows 'Afghan' being consistently capitalised with a frequency of well over 90%.

Grant 🚫

@Vincent Berg

Well, I wouldn't say 'facts', as those are observable and repeatable phenomena, whereas word choices are an individual choice,

Force= mass * acceleration.
It isn't about word choice, it's about one of the basic constants of our universe.
Each of those words has a particular definition and meaning. Unless you choose another word with the exact same meaning & definition, it would be wrong.

Replies:   Vincent Berg
Vincent Berg 🚫

@Grant

Force= mass * acceleration.
It isn't about word choice, it's about one of the basic constants of our universe.
Each of those words has a particular definition and meaning. Unless you choose another word with the exact same meaning & definition, it would be wrong.

The message I was responding to, included below, wasn't about your 'statement of fact', instead you'd broadened your complaint to general 'misstatements' in science fiction stories.

@Grant

There have been one or 2 stories that were meant to be Science fiction, but some of what was written was just so wrong I bailed out.

All I was arguing was, give the authors the benefit of the doubt. I often find myself misstating details I know are wrong (most often, using the term "theory" for a general idea). However, if an author keeps stating things that are clearly wrong, then yes, I'd agree it's not worth continuing as they haven't done the basic research the story requires.

Vincent Berg 🚫

@Zom

Thanks CW. It's happening a lot lately, and sometimes by authors that I expect would know better. I try not to be a grammar Nazi at large, but will consider your advice.

My editors catch a lot of things like that, where I definitely know better, but my fingers seem to have a mind of their own, as words and phrases get mangled between my brain to my fingers. Especially when the words are similar, so the difference isn't immediately apparent (like homophones).

MarissaHorne 🚫

The problem for the OP is that, while he is correct in criticising the statement "force equals mass times inertia" his proposed correction is just as wrong.

The equation is{ -

Force equals mass times acceleration

where acceleration is the change in velocity over time, measured in distance per time squared.

Momentum is mass times velocity.

Ernest Bywater 🚫

@Zom

Is there some reason, other than ignorance, that folk are using 'inertia' in a way that seems entirely inappropriate? Has some US state legislated a change in the naming of SI units? What is going on?

Probably poorer education, or faulty memory by the aged who haven't looked at that stuff in 50 years. I hope you emailed the author about the error so they can fix it.

Replies:   Zom  sejintenej
Zom 🚫

@Ernest Bywater

I hope you emailed the author about the error so they can fix it.

The particular author that finally prompted this thread published the subject story in 2005, so I suspect any suggestions along those lines might be a touch late :-)

I don't like to proof uninvited, unless I want to proof for a particular author, and then I make a meal of it. I'm sure there are plenty of others who will take up my slack.

Vincent Berg 🚫

@Zom

The particular author that finally prompted this thread published the subject story in 2005, so I suspect any suggestions along those lines might be a touch late :-)

I don't like to proof uninvited, unless I want to proof for a particular author, and then I make a meal of it. I'm sure there are plenty of others who will take up my slack.

If the author is no longer active on SOL, then you have a point. But, if someone finds something in a story I wrote ten years ago, I'd want to know so I can make a quick correction.

As for 'not wanting to proof a story uninvited', I always approach suggesting corrections cautiously (since many respond, while others don't). Generally, I'll start out by suggesting one or two changes that stand out, and if the author responds I'll then send more (figuring they're interested). If they ignore the message, or don't make the change, I mark them in my 'Do Not Contact' list.

However, this is often how I find many of my full-time editors. They start off as regular readers who know a particular subject and offer 'single corrections' over time.

Ernest Bywater 🚫

@Zom

The particular author that finally prompted this thread published the subject story in 2005, so I suspect any suggestions along those lines might be a touch late :-)

Some authors, like myself, will fix errors no matter how old they are. However, there are also some who'll never fix any errors.

Replies:   Michael Loucks
Michael Loucks 🚫

@Ernest Bywater

Some authors, like myself, will fix errors no matter how old they are. However, there are also some who'll never fix any errors.

I'll fix 'em until I die. Unfortunately, the errors NEVER seem to die, even with good editors and proofreaders! Sigh...

sejintenej 🚫

@Ernest Bywater

@Zom

Is there some reason, other than ignorance, that folk are using 'inertia' in a way that seems entirely inappropriate?

Perhaps slang, just as centrifugal is used when the correct word is centripetal (how many ordinary people have even heard of centripetal?)

Has some US state legislated a change in the naming of SI units? What is going on?

Some states have done sensible things and some have legislated nonsense. As examples I think it was Illinois which changed the name of their language to "American" whilst another has legislated that Pi (the mathematical constant) shall be 3 and not 3.14159 etc.

Probably poorer education, or faulty memory by the aged who haven't looked at that stuff in 50 years.

Certainly in my time educational standards here have fallen very badly.

Replies:   Vincent Berg  Zom
Vincent Berg 🚫

@sejintenej

As examples I think it was Illinois which changed the name of their language to "American" whilst another has legislated that Pi (the mathematical constant) shall be 3 and not 3.14159 etc.

If Pi was three, it wouldn't been called "Three". It's not, hence it's called "Pi", which refers to a specific numerical occurrence.

Legislatures may not be ignorant themselves, but they certainly like preferring legislating it!

Replies:   Zom
Zom 🚫
Updated:

@Vincent Berg

whilst another has legislated that Pi

It was Indiana, and the bill was never voted into effect. It wasn't actually about Pi, but the value for Pi (3.2) fell out of the substance of the bill, which was about squaring of the circle. I have no understanding at all why anybody would want to legislate such a thing, but am thankful to Professor C. A. Waldo for enforcing speculative INETRTIA, and causing the bill to fail.

Replies:   sejintenej
sejintenej 🚫

@Zom

It was Indiana, and the bill was never voted into effect. It wasn't actually about Pi, but the value for Pi (3.2) fell out of the substance of the bill, which was about squaring of the circle. I have no understanding at all why anybody would want to legislate such a thing, but am thankful to Professor C. A. Waldo for enforcing speculative INETRTIA, and causing the bill to fail

I was actually thinking of Alabama.
Responding to pressure from religious groups, Alabama's state legislature redefined the value of pi from 3.14159 to :-( 3 in order to bring it in line with Biblical precepts.


mea culpa - I should have checked Snopes :-(

Replies:   Vincent Berg
Vincent Berg 🚫

@sejintenej

I was actually thinking of Alabama.

Ah, yes, Alabama, the proverbial cesspool of intelligence and knowledge.

There are a few intelligent people there, but they don't admit it in public often.

Replies:   richardshagrin
richardshagrin 🚫
Updated:

@Vincent Berg

Mississippi exists so Alabama does not have the lowest statistics in the USA.

Replies:   Zom
Zom 🚫

@richardshagrin

Mississippi exists so Alabama does not have the lowest statistics in the USA

Yes, Mississippi does have a lower elevation rank (47) than Alabama (35), but sadly is not the lowest, which is Florida (51).

Zom 🚫

@sejintenej

centrifugal is used when the correct word is centripetal

Interestingly, both words are 'correct' and refer to opposing forces. In a rotating system, like a rock swung on the end of a string, centrifugal is the (apparent) force that causes an object to want to move further away, and centripetal is the force (provided by the string) that prevents it moving away and keeps it following the arc. At least that's what they were back when I was in school. Maybe they have changed since then. Although I suspect there is great INERTIA to changing physics terms.

Replies:   Not_a_ID
Not_a_ID 🚫
Updated:

@Zom

Interestingly, both words are 'correct' and refer to opposing forces. In a rotating system, like a rock swung on the end of a string, centrifugal is the (apparent) force that causes an object to want to move further away, and centripetal is the force (provided by the string) that prevents it moving away and keeps it following the arc. At least that's what they were back when I was in school. Maybe they have changed since then. Although I suspect there is great INERTIA to changing physics terms.

Apparent is the operative part, there is no such thing as a "centrifugal force" although there can be centrifugal effects. Any "force" being experienced is centripetal in nature as something acts to keep the item within a fixed distance from the center of rotation.

Centrifugal "force" is called a "false force" in physics for a reason, it's an illusion.

Replies:   Zom
Zom 🚫

@Not_a_ID

Centrifugal "force" is called a "false force"

Interesting. Do you have a reference for that?

My understanding is that it is an apparent force developed by an object's inertia when a centripetal force maintains a curvilinear motion instead of a straight vector.

Surely, if there was no 'centrifugal force' applying, apparent or otherwise, bodies would not need a centripetal force to maintain curvilinear motion.

It's only 'apparent' because it is a derived force, rather than a direct force. I'm sure that blood cells in a separation centrifuge don't care if it's apparent or not. They press on regardless :-)

Replies:   Vincent Berg
Vincent Berg 🚫

@Zom

Interesting. Do you have a reference for that?

My understanding is that it is an apparent force developed by an object's inertia when a centripetal force maintains a curvilinear motion instead of a straight vector.

I suspect they're 'generational' terms, as one generations scientists got fed up with the old definition, thinking it not specific enough. (Though, of course, I have zippo references for my supposition.) 'D

Harold Wilson 🚫

@Zom

Check wikipedia.

In the age of relativity, mass and energy have been unified. There is a place for the mass-equivalent in force, but 'inertia' is the term used. Force is the product of inertia and acceleration, in simple scenarios.

Force is a vector, so "vectored speed" is appropriate to the discussion, but only as a starting point (acceleration is key).

Replies:   Zom
Zom 🚫

@Harold Wilson

Check wikipedia.

Did that:
"In classical mechanics, conservation of linear momentum is implied by Newton's laws. It also holds in special relativity (with a modified formula) and, with appropriate definitions, a (generalized) linear momentum conservation law holds in electrodynamics, quantum mechanics, quantum field theory, and general relativity. It is ultimately an expression of one of the fundamental symmetries of space and time, that of translational symmetry." My emphasis.

Perv Otaku 🚫

@Zom

Going back to my high school Newtonian physics, and paraphrasing badly: 'inertia' is the tendency to stay as you are, and 'momentum' is the tendency to keep going as you are. Force is required to change either. 'Velocity' is just vectored speed, and has little to do with 'inertia'.

Except that you are remembering it wrong. Inertia is "an object at rest stays at rest and an object in motion stays in motion, unless acted upon by an outside force".

Momentum is mass times velocity, which of course is a constant number DUE TO inertia, again unless an added force is causing positive or negative acceleration.

As for the later centrifugal vs. centripetal force argument, see https://www.explainxkcd.com/wiki/index.php/123:_Centrifugal_Force

Back to Top

 

WARNING! ADULT CONTENT...

Storiesonline is for adult entertainment only. By accessing this site you declare that you are of legal age and that you agree with our Terms of Service and Privacy Policy.


Log In