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Can someone explain why constant and non-constant torque are treated differently? Also, the article refers to equations of motion, but the torque/acceleration equation isn't really an equation of motion. Serrano24 ( talk) 17:39, 23 June 2008 (UTC)
which is now a differential equation. Differential equations of this form (second time derivative of position related to some -- possibly time varying -- sum of forces/torques) are what are refered to as "equations of motion", so I'm not sure I see why you say that the torque/acceleration equation isn't an equation of motion. Would something along the lines of what is above be a good addition to the section of the article on non-constant torques? -- GLeeDads ( talk) 16:18, 12 November 2008 (UTC)
The equation which gives angular acceleration as
is incorrect because it denotes as a scalar but the tangential acceleration as a vector. It is probably best to drop the bold and specify that is the magnitude of the tangential acceleration. I would just make this change myself, but I'm completely new to Wikipedia and don't know the etiquette yet. -- GLeeDads ( talk) 16:10, 12 November 2008 (UTC)
This isn't quite correct. Defining angular acceleration as:
(using the same nomenclature as above) is better in the sense that it does not incorrectly mix vectors and scalars, but incorrect in that it defines angular acceleration as a scalar. Angular acceleration, like angular velocity is a vector quantity. It specifies both the magnitude and direction of the time rate of change of the angular velocity (also a vector quantity). As it stands, the information on this page is only correct for the case of simple two dimensional rotation. For more general three-dimensional rotation, both the torque and angular acceleration need to be treated as vector quantities. Additionally, the inertia I, needs to be treated as a tensor, not a scalar quantity. As soon as I get some more time I'll try to write up a more complete page. —Preceding unsigned comment added by 171.66.54.243 ( talk) 20:40, 25 April 2011 (UTC)
The word Velocity has the connotation distance per unit time and therefor is not a good word to use about Angular acceleration, since Angular acceleration is about the time rate of change of the angle of direction of motion and not about distance. WFPM ( talk) 12:05, 30 April 2010 (UTC)
The comment(s) below were originally left at Talk:Angular acceleration/Comments, and are posted here for posterity. Following several discussions in past years, these subpages are now deprecated. The comments may be irrelevant or outdated; if so, please feel free to remove this section.
The equation shown for finding the angular acceleration is incorrect. |
Last edited at 02:47, 24 April 2007 (UTC). Substituted at 07:50, 29 April 2016 (UTC)
This
level-5 vital article is rated Start-class on Wikipedia's
content assessment scale. It is of interest to the following WikiProjects: | |||||||||||
|
Can someone explain why constant and non-constant torque are treated differently? Also, the article refers to equations of motion, but the torque/acceleration equation isn't really an equation of motion. Serrano24 ( talk) 17:39, 23 June 2008 (UTC)
which is now a differential equation. Differential equations of this form (second time derivative of position related to some -- possibly time varying -- sum of forces/torques) are what are refered to as "equations of motion", so I'm not sure I see why you say that the torque/acceleration equation isn't an equation of motion. Would something along the lines of what is above be a good addition to the section of the article on non-constant torques? -- GLeeDads ( talk) 16:18, 12 November 2008 (UTC)
The equation which gives angular acceleration as
is incorrect because it denotes as a scalar but the tangential acceleration as a vector. It is probably best to drop the bold and specify that is the magnitude of the tangential acceleration. I would just make this change myself, but I'm completely new to Wikipedia and don't know the etiquette yet. -- GLeeDads ( talk) 16:10, 12 November 2008 (UTC)
This isn't quite correct. Defining angular acceleration as:
(using the same nomenclature as above) is better in the sense that it does not incorrectly mix vectors and scalars, but incorrect in that it defines angular acceleration as a scalar. Angular acceleration, like angular velocity is a vector quantity. It specifies both the magnitude and direction of the time rate of change of the angular velocity (also a vector quantity). As it stands, the information on this page is only correct for the case of simple two dimensional rotation. For more general three-dimensional rotation, both the torque and angular acceleration need to be treated as vector quantities. Additionally, the inertia I, needs to be treated as a tensor, not a scalar quantity. As soon as I get some more time I'll try to write up a more complete page. —Preceding unsigned comment added by 171.66.54.243 ( talk) 20:40, 25 April 2011 (UTC)
The word Velocity has the connotation distance per unit time and therefor is not a good word to use about Angular acceleration, since Angular acceleration is about the time rate of change of the angle of direction of motion and not about distance. WFPM ( talk) 12:05, 30 April 2010 (UTC)
The comment(s) below were originally left at Talk:Angular acceleration/Comments, and are posted here for posterity. Following several discussions in past years, these subpages are now deprecated. The comments may be irrelevant or outdated; if so, please feel free to remove this section.
The equation shown for finding the angular acceleration is incorrect. |
Last edited at 02:47, 24 April 2007 (UTC). Substituted at 07:50, 29 April 2016 (UTC)