Talk:List of elementary physics formulae

Needs context

This article needs lots of context (annotations of what the equations mean, or at least explanations of the symbols, etc.). More importantly, it needs an explanation of what this page itself is—hopefully something more than a fairly unfocused/indiscriminate list. I'll hold off pushing for deletion, but not for long. DMacks 03:11, 25 January 2007 (UTC)

Oops, looks like people aren't willing to wait. DMacks 03:23, 25 January 2007 (UTC)

improve?

I'm working on it. Please help! --N Shar 04:11, 25 January 2007 (UTC)

• Gotta sign off for tonight soon. I'll be back, though. --N Shar 04:48, 25 January 2007 (UTC)

Thoughts

I'm not going to be much help on this page, but I do support keeping it. Do note that you have number of thigs to do here. One is to set a scope for it: This list should be for important equations. You should also be amenable to the concept of lists being created for the various subdisciplines to hold less signoficant equations.

You will also need to be open to the ideas of changing the name as well as determining which pages this should be referenced from (such as physics and classical mechanics). --EMS | Talk 19:28, 25 January 2007 (UTC)

Ok, let's start brainstorming then. Any ideas on what exactly is an "important" equation? enochlau (talk) 01:50, 26 January 2007 (UTC)

Here are some suggestions:

• Formulae should be as general as possible. Example: "$a={\frac {d^{2}x}{dt^{2}}}$", not "$a={\frac {2x}{t^{2}}}$ (constant acceleration)."
• Formulae should not overlap with others on the page. Example: don't include both "$v={\frac {dx}{dt}}$" and "$x=\int _{t_{i}}^{t_{f}}v(t)\,dt.$"
• Formulae should not be obvious from the definition of non-physical quantities. Example: don't include "$v_{avg}={\frac {1}{t_{f}-t_{i}}}{\int _{t_{i}}^{t_{f}}v(t)\,dt}$", which follows directly from the definition of the average of a function.
• As a "notability guideline" for formulas, let's say that multiple textbooks must list them in sections of "key formulas" or something like that. I'm a little concerned that this might be too expansive a definition of notability, but here's an example. A copy of Giancoli's Physics (5th ed), which is unfortunately algebra-only, lists the following formulae in the "Summary" of the rotational motion chapter:

• (1) $\omega ={\frac {\Delta \theta }{\Delta t}}$
• (2) $\alpha ={\frac {\Delta \omega }{\Delta t}}$
• (3) $v=r\omega \,$
• (4) $a_{tan}=r\alpha \,$
• (5) $a_{rad}=\omega ^{2}r\,$
• (6) $\omega =\omega _{0}+\alpha t\,$ (constant acceleration)
• (7) $\theta =\omega _{0}t+{\frac {1}{2}}\alpha t^{2}$ constant acceleration)
• (8) $\omega ^{2}=\omega _{0}^{2}+2\alpha \theta$ (constant acceleration)
• (9) $\omega _{avg}={\frac {\omega +\omega _{0}}{2}}\,$ (constant acceleration)
• (10) $\sum \tau =I\alpha$
• (11) $KE={\frac {1}{2}}Mv_{CM}^{2}+{\frac {1}{2}}I_{CM}\omega ^{2}$
• (12) $L=I\omega \,$
• (13) $\sum \tau ={\Delta L \over \Delta t}$

Fortunately, we can narrow this down a bit. Numbers (1), (2), and (13) should be calculified. Each of (3) and (4) can be deduced from the other, so one could be eliminated. Formulae (6) through (9) are not general, because they require constant acceleration. We should calculify and consolidate them. Number (11) conflicts with a formula from linear mechanics; since (11) is more general, the other formula should be removed or replaced with a link to (11). Finally, number (13) is just a restatement of (10) and (12).

Opinions? --N Shar 06:41, 26 January 2007 (UTC)

I would caution some care here, as you all treading on unstable ground. It seems that previous attempts to create a page like this have gotten deleted fairly quickly, but I will assume that they were nowhere near as organized and comprehensive as this article is. With the above list of formulae for rotational motion, you are threatening to make that section way to cumbersome. I would strongly advise restricting that section to the attributes of constant angular momentum. (The full sub-list could be a topic in its own right in theory.) Beyond that, I advise

• Giving each section a short introduction (1 - 3 sentences) introduction.
• Providing references to textbooks and handbooks that contain these formulae.
• Adding material on electronics and possibly electromagnetism.
• Only accept as sections subfields of physics which as considered to be important to theoretical physics.
• Restrict the contents of each section to the most important equations for each acceptable subfield.
• At some point either change the name to include "classical" or include equations from relativity and quantum mechanics.

I do wish you all well with this project. Please realize that you all are going to need keep this article "ahead of the curve" so to speak. If it stagnates in its current state, it will be deleted. In fact I can almost guarentee you all another deletion attempt within the next year, and I will not guarentee even my own support for this article at that time. Yet you all have done well so far, and I encourage you all to keep up the good work. --EMS | Talk 03:55, 28 January 2007 (UTC)

Why delete ?

I would like to understand why this article is to be deleted ? --npettiaux 20:42, 28 January 2007 (UTC)

• The discussion is at Wikipedia:Articles_for_deletion/List_of_physics_formulae eaolson 21:10, 28 January 2007 (UTC)

Re: move

I support the move. It resolves some of the issues from the AfD. I imagine that some people will not support it, so I've started this thread for discussion just in case. --N Shar 07:29, 5 February 2007 (UTC)

• Support - The new name is not my first choice, but it works nicely. --EMS | Talk 16:58, 7 February 2007 (UTC)

Merge elementary physics formulae into this article

This other article seems to be redundant with the scope of this one. The lead sections even read similarly. Does anyone know what reason they both exist that is still relevant? David Hollman (Talk) 23:07, 7 September 2010 (UTC)

• Merge. Reasons above. EryZ (talk) 07:18, 23 June 2011 (UTC)

new pointer

As a temporary solution to difficulties in editing and reading the article as it becomes increasingley larger, I added hide/show tabs to all the tables to cut down the size of the article, so people can read which table of formulae the need by looking under the headings and simply clicking on the table link, other wise the article is too big and easy to get lost into.

It should still be easy to edit by clicking on the most localized edit link and then editing the table, the code layout has been changed to make it easier to follow along the rows, each column seperated.

Again and as always, there is still lots to do...

Maschen (talk) 16:52, 22 May 2011 (UTC)

Dimensional size (height/width in pixels) is not the issue, but rather the byte count. Adding the hidden-table code only increases that. Also the show/hide buttons become more sluggish on an enormous page. I tried to copy-edit but the spell-checker in my web-browser gives up and stops underlining the misspelled words about halfway down. I recommend installing one so you can check your own spelling as you write. ―cobaltcigs 07:29, 27 May 2011 (UTC)

The poor spelling of mine can easily be resolved by using microsoft word, then copying and pasting to the editor. I never have used it thoughout extending the article, but will from now on.

Apologies, Maschen (talk) 15:29, 29 May 2011 (UTC)

Definitions have been removed, a new article Defining equation (physics) has been created and its move from userspace draft to mainspace is underway (hopefully will be successful), to accompany this article and to be used in conjunction with Constitutive equation and Continuity equation. It seems these classifications of equations are much neater.

Maschen (talk) 14:52, 16 June 2011 (UTC) Maschen (talk) 14:52, 16 June 2011 (UTC)

Article length

The article has significantly reduced in size now, so there is no need for the article size warning tab. Maschen (talk) 20:46, 29 July 2011 (UTC)

What a mess...

This article was the first I have ever edited just now. There was so much to clear up, more could probably be done..... More links will be added, further mistakes will corrected. I have a plan on how to condense the wave physics formulation, and will do so later, which seems to take up most of the article. The quantum mechanics section now seems to be the most ropey part of the article in presentation, which will be re-written most likley from scratch. F=q(E+v^B) (talk) 15:52, 14 September 2011 (UTC)

Lost content has returned

I transferred content from Mathematical descriptions of physical laws originally in this article back to here, that article was just pointless and wrong in places anyway. Yes clearly it is very long and I will try to shorten and amalgamate as many tables as possible in this article... please be patient and do NOT revert anything in the process, sources/etc will be incorperated... thank you...F = q(E+v×B) ⇄ ∑_ic_i 20:53, 6 May 2012 (UTC)

"the table was better before"

This string of edits (mostly by myself) was performed to bring the page into compliance with WP:Accessibility (a Manual of Style guideline), specifically WP:Accessibility#Unbulleted lists and WP:Accessibility#Tables (the latter of which references Wikipedia:Manual of Style/Accessibility/Data tables tutorial). I moved the small headers for a reason, and removed the width on top of that (as we should let the browser determine where to line break). As for "format is used throughout most of the article", I was working my way through the article, slowly but surely. Consistency is not a good reason for a reversion in this instance, given the reasoning above. F=q(E+vxB), please revert your reversion. --Izno (talk) 00:04, 15 May 2012 (UTC)

This is not the first time - at one point the format was name - nomenclature - equation. The reason was that the variables are immediately below the subject of the equation and the tables are more compact. Just to save you time I'll change it all back. F = q(E+v×B) ⇄ ∑_ic_i 05:35, 15 May 2012 (UTC)

By the way you removed the fixed widths of the columns in the table. Please at least leave those alone so the tables don't expand sideways too much. F = q(E+v×B) ⇄ ∑_ic_i 05:39, 15 May 2012 (UTC)

Please no-one edit this article for a while. I'm in the process of it now, if you do not see the change for some time it becuase I'm re-writing bits for clarity/completeness, on top of the table editing/listifying... its a big job. Thanks. F = q(E+v×B) ⇄ ∑_ic_i 07:35, 15 May 2012 (UTC)

Done for now, intend to finish more later (if no-one else does...), I havn't the time right now, maybe in a few days or so... F = q(E+v×B) ⇄ ∑_ic_i 09:46, 15 May 2012 (UTC)

I understand the desire for a more compact table, but that comes second place to accessibility.

As for fixed widths, I did so because we shouldn't be choosing the size to display the table at, the browser should, in almost all cases. --Izno (talk) 14:54, 15 May 2012 (UTC)

Content has been moved out everywhere

Please see edit history - too busy keeping everything under control. This article can sit here empty for a while... I'll move the sources out everywhere. Maschen (talk) 00:54, 15 September 2012 (UTC)

 Done Maschen (talk) 08:45, 18 September 2012 (UTC)