User talk:Aïki
From Wikipedia, the free encyclopedia
My edits with my IP.
Hi on a Talk page you added a subject "Reaction force and opposite force" in the middle of other, older comments. Please bottom-post, otherwise it won't be much noticed! Harald88 17:29, 8 January 2006 (UTC)
- 15:48, 17 January 2006 (hist) (diff) m E=mc² (→Using relativistic mass -m0) (top)
[edit] Centripetal force
Aiki, I reverted your today's edits on the centripetal force. They are wrong since
1. In any reference frame at which the object is rotating, it has a centripetal acceleration.
- Not in corotating frame of reference in which the object is at rest.
- I said "In any reference frame at which the object is rotating" (rotating = not at rest)
2. The word "net" in the net force is important. The centripetal force is in many cases not a single force, but a sum of many forces. Some of them may even point away from the axis of rotation.
- We can keep the 'net', because even if we have only one force, it could be called a net force.
- Right.
3. The term "center of the plane of rotation" is bad, because plane doesn't have a center. The correct term to use is "axis of rotation". The axis of rotation, by the way, is in general not an actual physical object, therefore saying "inside the axis of rotation" is not good.
- In the case of a ball rotating around a pivot, the pivot is a physical object.
- The example in the article is about a rope. The axis of rotation there is not a physical object, it's just a line is space.
- For the term "center of the plane of rotation", I will have to verify.
Yevgeny Kats 03:28, 2 February 2006 (UTC)
- Thank you for your comments. --Aïki 03:52, 2 February 2006 (UTC)
- Thanks for your answers. Next time please don't repeat your answer on my talk page. I'll watch yours. Good night! Yevgeny Kats 04:01, 2 February 2006 (UTC)
