Talk:Force/Archive 4

This is an archive of past discussions about Force. Do not edit the contents of this page. If you wish to start a new discussion or revive an old one, please do so on the current talk page.

Archive 1

Archive 2

Archive 3

Article listed at WP:GAR

In response ass

ScienceApologist's note on the GAN talk page, I have removed the current GA hold and instead listed Force at Good article reassessment, where it will receive wider attention from other GA reviewers.

The reasons I have taken this decision are elaborated in more detail on the GAN talk page, but to summarise, ScienceApologist's apparent disagreement with Awadewit's original GA review quick-fail, and the accompanying reversions to both the GA tag and the GA page nomination, would seem to imply that her decision is disputed. I have restored the GA fail tag - this should remain on the article even if it ultimately attains GA status, as it pertains to the article history and development. For future reference, it is also rather frowned upon to revert GAN page removals, since it implies the article was never reviewed and restores the original nom date (a complete re-nomination would have been more appropriate).

Regards, EyeSerene^TALK 10:45, 7 December 2007 (UTC)

I've closed the GAR. The consensus was not to list the article as GA, but to recommend renomination at GAN (as a fresh nomination). I disagree with EyeSerene about the fail tag since it states that "the article was not considered to be a good article at the time" and this had not actually been properly determined. I don't feel strongly about this, however, so if anyone does want to restore the fail tag, or even start an ArticleHistory template, with the GAN and the GAR, I won't complain. Geometry guy 19:58, 18 December 2007 (UTC)

No personal preference here; I was just restoring Awadewit's tag. I'll not quibble though ;) EyeSerene^TALK 08:26, 19 December 2007 (UTC)

GAN review

Resolved

– All issues have been addressed. ScienceApologist (talk) 20:49, 11 January 2008 (UTC)

The following discussion lists resolved GAN review issues. Subsequent comments should be made in a new section.

Done Instead, Newton's law is meaningful because it asserts the proportionality of two quantities which can be defined without reference to it.

This sentence needs to be reworded.

Done Thus, the intuitive Aristotelian belief that a net force is required to keep an object moving with constant velocity (therefore zero acceleration) is objectively wrong and not just a consequence of a poor choice definition. With rather more justification, Newton's second law can be taken as a quantitative definition of mass by writing the law as an equality, the relative units of force and mass are fixed.

Citation needed.

In this article Newton's laws of motion Newtons's third law is written entirely in prose. In this article Force the third law is written almost entirely mathematically. Could prose and mathematics be combined?
It is the opinion of at least one of the article's authors that this is not really necessary. ScienceApologist (talk) 10:57, 11 January 2008 (UTC)
Done While such set-ups allow for an increase in force the corresponding increase in distance associated with the greater length of string conserves energy as all simple machines must

Should be re-worded. (From Semiautomatic peer reviewer.)

Done Per Wikipedia:Manual of Style (numbers), when doing conversions, please use standard abbreviations: for example, miles -> mi, kilometers squared -> km², and pounds -> lb.^[?]
Done Per Wikipedia:Manual of Style (numbers), please spell out source units of measurements in text; for example, the Moon is 380,000 kilometres (240,000 mi) from Earth.^[?] Specifically, an example is 32.174 lb.
Done Per Wikipedia:Manual of Style (headings), headings generally should not repeat the title of the article. For example, if the article was Ferdinand Magellan, instead of using the heading ==Magellan's journey==, use ==Journey==.^[?]
Per WP:WIAFA, this article's table of contents (ToC) may be too long – consider shrinking it down by merging short sections or using a proper system of daughter pages as per Wikipedia:Summary style.^[?]
There are a few occurrences of weasel words in this article- please observe WP:AWT. Certain phrases should specify exactly who supports, considers, believes, etc., such a view.
- Done apparently
- might be weasel words, and should be provided with proper citations (if they already do, or are not weasel terms, please ~~strike~~ this comment).^[?]
Done Please make the spelling of English words consistent with either American or British spelling, depending upon the subject of the article. Examples include: meter (A) (British: metre), metre (B) (American: meter), recognise (B) (American: recognize), realize (A) (British: realise), traveled (A) (British: travelled).
Watch for redundancies that make the article too wordy instead of being crisp and concise. (You may wish to try Tony1's redundancy exercises.)
- Vague terms of size often are unnecessary and redundant - “some”, “a variety/number/majority of”, “several”, “a few”, “many”, “any”, and “all”. For example, “All pigs are pink, so we thought of a number of ways to turn them green.”
  Copyedit request made to resolve this issue. Some of these instances seem needed. It is unclear where they are not needed. ScienceApologist (talk) 10:57, 11 January 2008 (UTC)
- Done Avoid misplaced formality: “in order to/for” (-> to/for), “thereupon”, “notwithstanding”, etc. (From Semiautomatic peer reviewer.)
Done Forces can be classified as conservative or nonconservative. Conservative forces are equivalent to the gradient of a potential.

What are non conservative ones? 1 States non conservative forces in plain english... or 2 in examples.

Done Per Wikipedia:Manual of Style (numbers), please spell out source units of measurements in text; for example, the Moon is 380,000 kilometres (240,000 mi) from Earth.^[?] Specifically, an example is 32.174 lb.
Done Although there are apparently many types of forces in the Universe, they are all based on four fundamental forces.

Reword. The types of forces in the Universe are all based on four fundamental forces.

DoneSome astrophysicists predicted the existence of another planet (Vulcan) that would explain the discrepancies, but despite some early indications, no such planet could be found to exist.

Reword. Astrophysicists predicted the existence of another planet (Vulcan) that would explain the discrepancies however no such planet could be found to exist.

Done Some forces are modeled by making simplifying assumptions about the physical conditions.

re word...Forces can be modeled by making simplifying assumptions about the physical conditions.

Done Sometimes called the "second most famous formula in physics", Newton never stated explicitly the F=ma formula for which he is often credited.

Re word... The "second most famous formula in physics", Newton never stated explicitly the F=ma formula for which he is often credited.

Done In the section named Units of measurement. Is not the definition of a Newton the force that gives an acceleration of 1 m/s squared when acting on a 1 kg mass? That would be an easier form of prose. What is the most commonly used measurement?
Done In the section named Units of measurement. Add the measurement of torque the Newton meter (N.m) as the product of the force and the distance this force is from an axis of rotation.
Done In the section named Units of measurement. Can a table be made showing how the units fill in the equation. Such as...

Units of Measurement
System	Mass	Acceleration	Force
SI	kilogram (kg)	meter/second squared (m/s²)	Newton (N)
CGS	gram {(g)	centimeter/second squared (cm/s²)	dyne (dyn)
Imperial	pound (lb)	feet/second squared (ft/s²)	pounds force lbf
English	pounds mass	feet per second squared (ft/s²)	poundal {pdl) or (pl)
BE	slug {sl}	feet per second squared (ft/s²)	pound (lb)

Done Should units of measurement be included such as a sthene (1000 newtons), kip (1000 pound-force) and kilopond (gravitational force on a mass of one kilogram) units unit 2
Done The origin of electric and magnetic fields would not be fully explained until 1864 when James Clerk Maxwell finally unified a number of earlier theories into a succinct set of four equations that fully described the sources of the fields as due to stationary and moving charges as well as the interactions of the fields themselves.

Re word. The origin of electric and magnetic fields would not be fully explained until 1864 when James Clerk Maxwell unified earlier theories into a succinct set of four equations that described the sources of the fields as due to stationary and moving charges and the interactions of the fields themselves.

Done When the standard g (an acceleration of 9.80665 m/s²) is used to define pounds force,

The definition ofg as the force of gravity should be stated.

DoneHowever, attempting to reconcile electromagnetic theory two observations, the photoelectric effect and the ultraviolet catastrophe, proved troublesome

This paragraph starting with the above sentence needs citations.

Done There are also a number of forces which are frame dependent, meaning that they appear due to the adoption of non-Newtonian (that is, non-inertial) reference frames.

Re word. There are forces which are frame dependent, they appear due to the adoption of non-Newtonian (that is, non-inertial) reference frames.

Done Below are several conversion factors between various measurements of force:

Re word. Conversion factors between various measurement systems of force:

Done Several theories were discussed over the centuries, and the late medieval idea that objects in forced motion carried an innate force of impetus was influential on the work of Galileo.

Re word. Amongst physics theories, the late medieval idea that objects in forced motion carried an innate force of impetus was influential on the work of Galileo.

Done Historically, forces were first quantitatively investigated in conditions of static equilibrium where several forces canceled each other out.

re word. Historically, forces were first quantitatively investigated in conditions of static equilibrium where forces canceled each other out.

Done using such tools, several quantitative force laws were discovered:

Re word using such tools, quantitative force laws were discovered:

Done As has been shown by many failed free quark searches, the elementary particles affected are unobservable directly.

Re word. Demonstrated by free quark searches, the elementary particles affected are unobservable directly.

Done As with all vector addition this results in a parallelogram rule:

Re word. Vector addition results in a parallelogram rule:

Done All these were all formulated and experimentally verified before Isaac Newton expounded his three laws of motion

Re word. These were formulated and experimentally verified before Isaac Newton expounded his three laws of motion

Done This was contrary to Aristotle's notion of a "natural state" of rest that all massive objects naturally approached.

Re word. This was contrary to Aristotle's notion of a "natural state" of rest that massive objects naturally approached.

Done Friction is a surface force that opposes motion. The frictional force is directly related to the normal force which acts in order to keep two solid objects separated at the point of contact.

Re word. Friction is a surface force that opposes motion. The frictional force is directly related to the normal force which acts to keep two solid objects separated at the point of contact.

Physics is constantly growing and expanding since Newton's three laws, and there are several more theories and laws than just those belonging to Newton. Therefore this article should show that there are several more articles and references for someone to learn about physics and force in particular, and one text book is not the bible of physics force. Another text or web page may explain a concept differently shed a different light on the matter, assist the reader better. More reference sources would be akin to having more than one professor or more than one tutor to explain the concept in a different way.
Not actionable. ScienceApologist (talk) 10:57, 11 January 2008 (UTC)
Done One reference is used a bizzillion times. There must surely be web sites and other texts that say something about force to show

that there is notability about force from more than just one place.

As there are four force types...strong, electromagnetic, weak, and gravitational mentioned in the lead paragraph, it would be convenient to have a table of contents link for more info on them.
There already is a table of contents link for fundamental models. ScienceApologist (talk) 10:57, 11 January 2008 (UTC)
Should dynamometers be mentioned as a method of measuring the force.

Done Can more pictures be used? Spring force can be shown, string or pulley force can be shown in vector diagrams, etc.
DoneAs well as friction force, should also tensile and compression force be discussed for the types of force acting on an object?

The above discussion lists resolved GAN review issues. Subsequent comments should be made in a new section.

I will look at this article again, this is a beginning.

GA review (see here for criteria)

This is a nice piece of work, but it still has some shortcomings with respect to the good article criteria.

It is reasonably well written.
a (prose): b (MoS):
It is factually accurate and verifiable.
a (references): b (citations to reliable sources): c (OR):
One source is used over and over. For an article this long, more references should be used.
It is broad in its coverage.
a (major aspects): b (focused):
It follows the neutral point of view policy.
Fair representation without bias:
It is stable.
No edit wars etc.:
Done It is illustrated by images, where possible and appropriate.
a (images are tagged and non-free images have fair use rationales): b (appropriate use with suitable captions):
Overall:
Pass/Fail:
Good luck improving the articleSriMesh | talk 02:06, 27 December 2007 (UTC)

some issues addressed, however not all, especially citations. Therefore processed a fail article verdict and removed from on hold status.SriMesh | talk 01:55, 3 January 2008 (UTC)

This again shows, that the GA review process is partially useless for articles about textbook physics. Judging the verifiability level to be "original research" because one standard textbook (by Feynman no less) is given as source is nonsense. In fact any inline references for this stuff is nonsense. This article is textbook physics, because you can go to the library of your physics department and take any textbook on mechanics and you'll find it to agree with the article. This is a level of reliability which cannot be documented by inline references. In fact, if you start to diversify the inline references by attributing different paragraphs to different textbooks this is near tio implying that these textbooks doesn't agree or doesn't give evidence for any chapter. --Pjacobi (talk) 13:16, 3 January 2008 (UTC)

We had this comment about a feature article which recently went under review as it didn't have enough citations to verify notability and needs Substantive reliable coverage. The article was Louis Riel and the review. The same was stated there as above, but in reference to biographies rather then science textbooks...The rationale was given that the bulk of the biography aligns with the consensus in all of the major biographies To preserve its feature status, citations were needed even if they were duh' and in every biography/textbook. If they are in every textbook, cite a few....which is what I am helping out with. SriMesh | talk 02:35, 5 January 2008 (UTC)

At the rate of change that this article is improving, it should soon achieve all comments made at all GAN, and if it is nominated again should pass soon. It was awkward to be processing close to the holiday season, should have extended the hold longer - sorrySriMesh | talk 02:41, 5 January 2008 (UTC)

This article suffers due to a lack of an overview section.

I find that some important aspects of forces have been left out. These relate mainly to the comparsion of the different forces. There is some info provide on this in the intro but it is very sketchy and lacks flow which makes it difficult for the reader to follow.

Some of the basic points I find are missing about forces are:

- some forces like gravity come from particles having quality that comes in one flavor but others like electromagnetic come from qualities that have two flavors resulting in both repulsive and attractive forces.

- some forces like friction and pressure are macro particle results. In other words it takes a bunch of particle working in concert for them to have any meaning.

- some forces like electric charge induce seemly different forces like magnatism when in motion. Others like gravity don't.

I am sure people can come up with others too. Some of these are indeed covered in more specfic sections but I feel that if the reader is to arrive as quickly as possible to a feeling for what forces are they need to be up front.

--RobertJDunn (talk) 19:10, 2 January 2008 (UTC)

Some comments on a paragraph

"In free-fall, this force is unopposed and therefore the net force on the object is the force of gravity. For objects not in free-fall, the force of gravity is opposed by the weight of the object. For example, a person standing on the ground experiences zero net force since the force of gravity is canceled by the weight of the person that is manifested by a normal force exerted on the person by the ground.[1]"

Unless in a vacuum, objects in free fall are usually opposed by aerodynamic drag. Objects not in free fall very often have accelerations that are not only due to gravity. Canceled is an OK term mathematically, but conceptually the reader might envision eliminated not equal and opposed. Ward20 (talk) 05:25, 3 January 2008 (UTC)

This is tricky. In the case of aerodynamic drag, the object is not really undergoing free-fall. Thus, an object that has reached terminal velocity technically is not weightless, for example. "Free" fall implies that there are no external forces other than gravity. You are correct about the problems with the term "canceled" however. I'll change that. ScienceApologist (talk) 19:03, 3 January 2008 (UTC)

After researching free-fall a little more rigorously I agree with you.

However, the Merriam-Webster Dictionary definition has a little ambiguity in it, "1: the condition of unrestrained motion in a gravitational field; 2: the part of a parachute jump before the parachute opens"

And the Wikipedia free fall article is contradictory to this definition and contradicts itself.

Perhaps an included free-fall definition might be helpful to cope with the seemingly widespread misconception that I had. Ward20 (talk) 23:00, 3 January 2008 (UTC)

Referencing

Many of the references are 'shared' between three books, one of which is Sears & Zemansky's University Physics; though the current referencing doesn't show what is referenced to which work. I have a 6th edition of Sears & Zemansky and am proposing to separate out those statements which can be attributed to Sears & Zemansky. — BillC ^talk —Preceding comment was added at 23:09, 3 January 2008 (UTC)

The link to an online copy of Maxwell's A Dynamical Theory of the Electromagnetic Field points to a website run by an over-unity zero-point energy group. Admittedly, they are simply hosting a copy of Maxwell's treatise, but still... bad. I'll see if I can find a better site to link to tonight. At worst, we can remove the links altogether, since it's the book that's the reference, not the website. — BillC ^talk 19:19, 7 January 2008 (UTC)

Good catch, Bill! We should also remove all the links elsewhere at Wikipedia. Here's a place to help us find them all: [1]. ScienceApologist (talk) 19:47, 7 January 2008 (UTC)

Sentence needs re-wording

Done As the mathematical formalism for Coulomb's Law, physicists of the eighteenth and nineteenth century became interested in the electric field which could be used to determine the electrostatic force on an electric charge at any point in space.

Very long sentence, doesn't flow from section to section. SriMesh | talk 02:45, 5 January 2008 (UTC)

Skipping GA on to FAC

I think that this article is good enough to skip GA entirely. I posted a peer review request and a copyedit request. Hopefully those are answered within the next few weeks favorably and we can put this article up for featured status. ScienceApologist (talk) 10:59, 11 January 2008 (UTC)

Good idea, with the amount of work you've done, it's sure to be a FA. -- penubag 00:51, 12 January 2008 (UTC)

Comments

Below are some comments in response to SA's review request. I hope they're useful. The current version of the article has a lot of good stuff! Gnixon (talk) 20:23, 12 January 2008 (UTC)

Good comments. I like your ideas on reorganizing especially. I'll be working on these in the next few days. ScienceApologist (talk) 21:32, 12 January 2008 (UTC)

Lead

This is obviously the hardest section to write, and will probably be the last thing to fall into place. Nevertheless, here are some comments:

1st paragraph

"force is what" is a little awkward.
Is "lift, push, pull" a standard breakdown of types of forces outside of aerodynamics?
More or less. Push or pull is the typical breakdown. Lift was added by an aerospace afficionado and it is my opinion that it adds a little bit of conceptual flare. ScienceApologist (talk) 21:23, 12 January 2008 (UTC)
Maybe consult dictionaries for guidance on defining the term. Always difficult to define such a fundamental, well-known concept in a reasonable way.
Not only that, it's controversial. We have consulted dictionaries and the problem is that most dictionaries are a bit too imprecise in their formulations. We follow them to the extent that they offer good definitions. ScienceApologist (talk) 21:23, 12 January 2008 (UTC)
Try to convey that force is a thing that tries to make an object accelerate. (But say it better than that!)
The problem here is the idea that force is a "thing". It's not really a "thing" in the proper material sense. ScienceApologist (talk) 21:23, 12 January 2008 (UTC)
Maybe mention Newton's laws or classical mechanics right up front in order to place the concept.
Suggest moving torque, stress, etc., to a later paragraph in lead.

2nd paragraph

"is mathematically equal to" is imprecise. Is net force defined this way? Is this paragraph about net force or force in general? Why not identify this statement as Newton's 2nd law?
The distinction between net force and force is somewhat artificial. It's pedagogically clean, but conceptually it can lead to problems. When a force is balanced by another force, do any forces really exist? How do you know? ScienceApologist (talk) 21:23, 12 January 2008 (UTC)

3rd paragraph

Last two sentences are a little unwieldy

Possible Reorganization

1st paragraph: attempt general definition
2nd paragraph: specifics centered on Newton's laws
3rd paragraph: rotation, stress, etc.
4th paragraph: State the four forces. Say how modern theories have come to use other stuff.
Suggest leaving history for next section

History

General comments I like the organization: Archimedes, Aristotle, Newton, gravity, other fundamental forces, modern concepts. However, sometimes the explicit focus on the development of the concept is a little distracting. I think it's better to just say what Aristotle and Newton did, if you know what I mean.

1st par

How about saying how the concept of force "arose"?
Nobody knows. Forces are associated with machines, that's as good as it gets. ScienceApologist (talk) 21:27, 12 January 2008 (UTC)

2nd par

Could be simplified with something like "Aristotle further developed the concept of force to explain how objects could be made to deviate from their natural motion (wikilink somewhere)."
"theory" with its wikilink is a little generous here.
"These shortcomings..." makes it seem like the ancients recognized the flaw in Aristotle's force. Was that the case?
Ancients didn't, but pre-Galilean European medieval thinkers found flaws that they couldn't address because Aristotle was Catholic dogma (see impetus for example). Also some Islamic figures seemed to have inertia down pat. We can be clearer on this. ScienceApologist (talk) 21:27, 12 January 2008 (UTC)
Galileo should get his own paragraph
Did he actually perform the rolling balls experiments? I may be confused by the Tower of Pisa business.
Yes, he actually did roll balls down inclined planes. At least, if you believe what he wrote, he did. ScienceApologist (talk) 21:27, 12 January 2008 (UTC)

3rd par

Prefer to say directly what Newton did, excising "is recognized as", "to argue explicitly", "in essence", "first and only", and other qualifiers. This seems like a tough paragraph to write.

4th par

Put "gravity" right up front, in the first sentence. It's key to the whole history.

5th par

Good to discuss how modern theories don't lean on "force" like Newton and Maxwell did. I would be more explicit about it, discuss GR and QM more specifically.
Should explain role of unifying "forces" in development of physics since Maxwell, particularly 20th century, and mention that unifying GR/QFT is a grand goal.
Noether's theorem is definitely sexy, but way too technical here.
Focus on saying that gravity is explained by dealing with energy-momentum; strong/electroweak explained within QFT (hard to do this well).

Descriptions

Newton's laws need to come before the other stuff.

Organization

Taking a break from specifics and looking over the article, I have a proposal for reorganizing the topics:

1) Lead
2) Pre-Newtonian concepts of force
   2.1) Archimedes
   2.2) Aristotle
   2.3) Galileo
3) Force in Newtonian Mechanics
   3.1) Newton's laws
   3.1.1) Statics
   3.1.2) Dynamics
   3.2) Gravity
   3.3) Electromagnetism
4) Forces in Modern Physics
   4.1) Strong and Weak Nuclear Forces
   4.2) Modern Reformulations
      4.2.1) GR
      4.2.2) QFT
      4.2.3) Unification

History could be woven in throughout, particularly in the intros of Sections 3 and 4, and "four forces" could be mentioned in the Section 4 intro. Possibly Gravity and E&M could go into a "Classical Forces" section, but I think they work in Section 3, where one wouldn't be tempted to delve deeply into QED too early. The current article's content would all fit nicely in these sections.

Rotations and torque

This section is a nice description of the ideal case shown in the animation, but does not state clearly the force of gravity of the ball (which is not massless) and its resulting couples are not shown. Suggest in animation that be explained. Ward20 (talk) 19:19, 26 January 2008 (UTC)

GAN

This article was placed for GA review at Christmas, and my hold could have been extended. As all items are done and attended to, and now there is now another awesome idea on this page...please re-register it for GA review, so it can be passed, as I feel it is at GA IMHO, and let me know, and I'll send it to the GA page. Kind Regards...SriMesh | talk 01:14, 15 January 2008 (UTC)

Do we want to think about implementing Gnixon's peer review comments first? Sadly, it appears ScienceApologist has left the project and will not be here to implement them himself. — BillC ^talk 01:22, 15 January 2008 (UTC)

If nobody else is available, and if nobody objects, I may start trying to do that reorganization. Of course, if others want to do it, even better (and if people object, no problem). I wouldn't likely get to it until next week. Not sure whether I'd officially rate the article "good" just yet, but that's only one opinion. Glad to see there's interest in continuing to improve it. Gnixon (talk) 14:37, 18 January 2008 (UTC)