Talk:Newton's laws of motion

Split proposal

Greetings! When I came across this page, I'm rather surprised that there are no individual articles for all three laws. This notion is simply due to the fact that they are so important, and should deserve individual articles for more detailed description. However, I'm not very sure, so I'm asking for opinions here. Pygos (talk) 11:03, 28 January 2025 (UTC)[reply]

This page, of course, shall remain, as it describes the underlying assumptions of the laws and their historical background. Pygos (talk) 11:07, 28 January 2025 (UTC)[reply]
The article is really an introduction to Newtonian mechanics, which happens to be described in three parts. Each individual law is not, by itself, useful or interesting. I believe three articles would end up being mostly repetition in order to explain how each law contributes to what is a single thing. Johnjbarton (talk) 16:38, 28 January 2025 (UTC)[reply]
The three laws together form a conceptual unit. Each one really needs to be understood in the context of the others. Splitting them into separate articles would make for needless repetition. XOR'easter (talk) 20:07, 28 January 2025 (UTC)[reply]
@Pygos It seems that your proposal did not get traction. Would you consider removing the tag in the article? Johnjbarton (talk) 02:03, 7 March 2025 (UTC)[reply]
Done Pygos (talk) 04:32, 7 March 2025 (UTC)[reply]
how do i close this discussion Pygos (talk) 02:04, 18 March 2025 (UTC)[reply]
 Done Dolphin (t) 03:16, 18 March 2025 (UTC)[reply]

A Possible Corrected and or Refined Restatement on the First Law of Motion

The original:

  1. A body remains at rest, or in motion at a constant speed in a straight line, unless it is acted upon by a force.

The corrected and or refined restatement:

  1. A body remains at rest and or in motion at a constant speed in a straight line, unless it is blocked by another body and or acted upon by a force.

Consider this philosophical anecdote from the African fable The Lion, the Hyena and the Rabbit: https://web.archive.org/web/20250622233431/https://www.worldoftales.com/African_folktales/African_Folktale_41.html#gsc.tab=0

... "I am thinking," said he, with a grave, philosophical air, "about those two stones, one big and one little; the little one does not go up, nor does the big one go down."....

The apple which fell during Newton's discovery got blocked by the earth (supposedly by his head in humourous version). So force and or blockage is necessary for the phenomenon to occur. — Preceding unsigned comment added by 106.222.223.16 (talk) 12:43, 25 July 2025 (UTC)[reply]

"Blockage" occurs when the blocker exerts a force during the collision. DMacks (talk) 12:51, 25 July 2025 (UTC)[reply]

Restating Newton's First, second and third law.

Newton's first law of motion should be:

When an object is at rest or in motion, it will remain in that state at an uniform velocity unless another force acts on it

Newton's second law should be: 'when a resultant force acts on an object, it causes the object to accelerate in the direction of the net force, the acceleration is directly proportional to the net force and inversely proportional to mass provided the mass remains constant. Furthermore, when the net force acting on an object is directly proportional to the change in it's momentum and inversely proportional to the time interval at which it acts

Newton's third law of motion should be:

For every action, there is an total opposite reaction that is equal in magnitude and opposite in direction

I also ask for Newton's laws of motion to have their articles so that they can explained into detail perfectly. Milk 12jaxe (talk) 18:00, 12 September 2025 (UTC)[reply]

The existing versions have copious citations so you will either need to convince us that the sources are wrong or the summaries of those sources are wrong. Johnjbarton (talk) 18:09, 12 September 2025 (UTC)[reply]
Your statement of the first law is confusing. It refers to "another force", but what was the first force then? Likewise, in your statement of the second law, everything after "Furthermore" is unclear. The second law relates the net force at a given time to the acceleration at that time; it doesn't itself involve a "time interval", though of course one can then go on to consider a force being applied throughout the duration of a time interval. Your statement looks like a garbled version of the idea that force is the rate of change of momentum with respect to time. Your statement of the third law is the colloquial saying "for every action there is an equal and opposite reaction", which is an oversimplification. It leaves out the very important fact that the action applies to one body while the reaction applies to another. (The article already explains this. It also provides sources, including a discussion in a free online textbook.)
Newton's three laws are taught together, and in practice they are used together. Moreover, they all rely on the same concepts: velocity, mass, acceleration, force. If we had separate pages for each of them, we'd have to explain all of those terms three separate times. Therefore, it makes sense to explain them all in the same article. (A split was proposed a few months ago and rejected.) Stepwise Continuous Dysfunction (talk) 19:53, 12 September 2025 (UTC)[reply]
@Milk 12jaxe can you explain why you think these restatements are improvements to how they are currently expressed? They seem very much worse to me. They are less clear and less precise, and some parts are even grammatically incorrect. For example, in your second law, the first sentence seems to be two sentences joined by a comma splice before the words "the acceleration". It's not clear what you mean by "a resultant force" (resultant to what?). The word "at" in "time interval at which it acts" is unclear; perhaps you mean "during"? (And minor points, but "it's" should be "its" and the final period is missing.) In your third law, the meaning of the word "total" is unclear. (And "an" should be "a" and another period is missing).
Overall, these seem poorly written and more likely to confuse the reader than help them understand. In what source did you find these versions of the laws? CodeTalker (talk) 20:01, 14 September 2025 (UTC)[reply]

Moving a paragraph of History.

The second paragraph of the History section starts out

  • As noted by scholar I. Bernard Cohen, Newton's work was more than a mere synthesis of previous results; ...

The paragraph is not about Newton's laws of motion and not about the history of the laws of motion. It is a summary of an argument against a naive historical analysis of Newton's approach to science. It has two solid sources but it is out of place here. I moved it to History_of_classical_mechanics where it makes a nice improvement.

The Footnote in the preceding paragraph has a similar problem. Again it is not about the history of Newton's laws at all. It is about Newton's model of the solar system but only as an example of why "intervention" or "experiments" are a vital aspect of theory building in physics. It does not belong here. Johnjbarton (talk) 02:05, 11 November 2025 (UTC)[reply]

Regarding the latter: It wasn't about the history of Newton's laws, in that it explains how experiments (active interventions) were necessary in order to go beyond what could be deduced from passive observations. It was not about "Newton's model of the solar system", but rather how science moved beyond a mere "model of the solar system" to universal laws. Makes sense enough to me.
Regarding the former: I don't see how it fails to be "about Newton's laws". The source argues that the ideas in Newton's laws are transformations, rather than mere recapitulations, of earlier notions. Examples are Newton's transformation of Keplerian "inertia" (by which bodies come to rest when the motive force ceases to act) to a kind of "inertia" (or "force of inertia") by which a body maintains its "state of motion" in the absence of an external force... (p. 160). It's a discussion "about Newton's laws of motion" and the rest of the programme Newton implemented in the Principia. I'd maybe prefer a statement based on more recent scholarship than I. Bernard Cohen, but in principle, it's appropriate. Stepwise Continuous Dysfunction (talk) 21:59, 20 November 2025 (UTC)[reply]
My primary objection to the Cohen content was its supposition " more than a mere synthesis ". To need this point we have to build the context that someone thought it was synthesis, and that leads us down a rabbit hole of he-said/she-said historical analysis. That analysis belongs elsewhere. Here we should speak directly to the laws. Rather than the meta "Examples are...", we should explain how Newton's inertia differs from Kepler's. Johnjbarton (talk) 00:11, 21 November 2025 (UTC)[reply]
allikas: https://en.wikipedia.org/wiki/Talk:Newton%27s_laws_of_motion