Talk:Force

From Wikipedia, the free encyclopedia

	This article has been identified by the Version 1.0 Editorial Team as a Core Topic, one of the 150 most important articles for any encyclopedia to have. Please help improve this article as we push to 1.0. If you'd like help with this article, you may nominate it for the core topics collaboration.
B	Force has been rated as B-Class on the assessment scale.

	This article is within the scope of WikiProject Physics, which collaborates on articles related to physics.	Physics Portal
B	This article has been rated as B-Class on the assessment scale.
Top	This article is on a subject of top importance within physics.
Help with this template This article has been rated but has no comments. If appropriate, please review the article and leave comments here to identify the strengths and weaknesses of the article and what work it will need.

This article is part of WikiProject Science, a project to improve Wikipedia's articles related to Science. For guidelines see the project page and Wikipedia:Contributing FAQ.

This article has been selected for Version 0.5 and the next release version of Wikipedia. This article has been rated B-Class on the assessment scale.

---

Earlier talk archive at

• Archive 1
• Archive 2

[edit] Units of measurement section

IMO the units of measurement section is much too long, and gives disproportionate weight to silliness like the use of kg as a unit of force.--24.52.254.62 00:17, 4 November 2006 (UTC)

[edit] Rotation

As the article stands it says a force causes an object to rotate, and this is not accurate. No force is needed to keep an object spinning, such as in a gyroscope for instance. A force is needed to keep an object orbiting however. Both these motions however are called rotation. I'm not quite sure how to phrase it to make it accurate. Any suggestions? Roy Brumback 08:47, 6 November 2006 (UTC)

In my opinion, the first sentence of the article should be simple. If you apply a force on a body that is not rotating, it may start rotating. This is what the sentence says, and I think it's good. I would suggest discussing the point mentioned by Roy Brumback later in the article. Yevgeny Kats 15:55, 6 November 2006 (UTC)

I agree it should be simple, but not at the expense of accuracy. As it's written, it makes it sound like a force it necessary to keep it rotating, which is not true in the case of spin. Roy Brumback 00:36, 7 November 2006 (UTC)

I've made a stab. I think the key is to emphasise the difference between a point particle and an extended body. A point particle doesn't rotate. The points in the gyroscope keep spinning because of the centrepetal force being provided by the structure of the metal. A gyroscope needs forces to keep spinning, they are just internal stresses. A "see also" bit pointing to moment would be good too.Rpf 14:11, 8 November 2006 (UTC)

This must be one of the hardest articles in Wikipedia to write. There are two issues; firstly it is meaningless to talk of motion without indicating what datum we are using for reference, i.e. the idea of inertial frames is necessary before moving on to force. Secondly, whilst in Newtonian mechanics force is viewed as the 'cause' of motion, modern field theories treat it more as a derived quantity, so to cover both contexts it becomes both 'cause' and 'effect'. If we treat force as an 'effect' in Newtonian mechanics, we end up with a circular argument defining mass. I think we can sacrifice rigour and retrict ourselves to the Newtonian world view. Sorry I can't help more, you are doing a great job. Gordon Vigurs 08:18, 8 December 2006 (UTC)