Talk:Work (physics): Difference between revisions

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::::Yes, in Holland we see coworkers and contraworkers (the latter often spotted  among flocks of civil servants).--[[User:Paul Wormer|Paul Wormer]] 06:04, 6 July 2009 (UTC)
::::Yes, in Holland we see coworkers and contraworkers (the latter often spotted  among flocks of civil servants).--[[User:Paul Wormer|Paul Wormer]] 06:04, 6 July 2009 (UTC)
== Britanica text ==
On the whole we, at CZ, see the Britanica as our role model. The Britanica gives the following for "work" (note its readability or lack thereof):
<blockquote>
in physics, measure of energy transfer that occurs when an object is moved over a distance by an external force at least part of which is applied in the direction of the displacement. If the force is constant, work may be computed by multiplying the length of the path by the component of the force acting along the path. Work done on a body is accomplished not only by a displacement of the body as a whole from one place to another but also, for example, by compressing a gas, by rotating a shaft, and even by causing invisible motions of the particles within a body by an external magnetic force.
No work, as understood in this context, is done unless the object is displaced in some way and there is a component of the force along the path over which the object is moved. Holding a heavy object stationary does not transfer energy to it, because there is no displacement. Holding the end of a rope on which a heavy object is being swung around at constant speed in a circle does not transfer energy to the object, because the force is toward the centre of the circle at a right angle to the displacement. No work is done in either case.
The mathematical expression for work depends upon the particular circumstances. Work done in compressing a gas at constanttemperature may be expressed as the product of pressure times the change in volume. Work done by a torque in rotating a shaftmay be expressed as the product of the torque times the angular displacement.
Work done on a body is equal to the increase in the energy of the body, for work transfers energy to the body. If, however, the applied force is opposite to the motion of the object, the work is considered to be negative, implying that energy is taken from the object. The units in which work is expressed are the same as those for energy, for example, in the metre-kilogram-second system, joule (newton-metre); in the centimetre-gram-second system, erg (dyne-centimetre); and in the English system, foot-pound.
</blockquote>
--[[User:Paul Wormer|Paul Wormer]] 06:33, 6 July 2009 (UTC)

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What about the other sort of work?

Any plans on how to disambiguate from the other sort of work - you know, the boring kind that we all have to do. –Tom Morris 08:29, 3 July 2009 (UTC)

Yes, I made a mistake, I will move.--Paul Wormer 09:52, 3 July 2009 (UTC)

Lead should be in everyday language understandable by the target reader.

It seems to me that the definition of work, along with examples, should be given and explored in the lead before the math is entered into the balance of the article. I took the liberty of demonstrating what I mean in the rewritten lead, as you can see. Not being a physicist, I used the examples that sprang to mind to explain the subject. If they fall off the mark, they can certainly be changed, but I hope the CZ community agrees that the introductory section, at least, should be written in plain English. Sincerely, your friend, George Garrigues 07:36, 5 July 2009 (UTC)

I hope that more articles on "work" will appear (economic, sociological, etc.) together with a disambiguation page (like energy). It seems to me that George's lead would be more appropriate either in the disambig or in the sociologically oriented article. Note that the title (physics in parentheses) narrows down the present article considerably. To me the comparison of a force in physics with the "police force" [which BTW only works (no pun) in English] is a bit far fetched in the context of a physics article.--Paul Wormer 09:26, 5 July 2009 (UTC)
On second thought, I started a disambiguation page and moved George's lead-in to there, and reverted the present page. I reverted because George removed the (for a physicist essential) sentence about the dimension and units used for "work (physics)" and removed also the essential adjective "magnetic" (non-magnetic particles do not align along a magnetic field). --Paul Wormer 09:53, 5 July 2009 (UTC)
Negative work isn't limited to physics; I've had several managers good at negative work. See Dilbert. Howard C. Berkowitz 02:10, 6 July 2009 (UTC)
Yes, in Holland we see coworkers and contraworkers (the latter often spotted among flocks of civil servants).--Paul Wormer 06:04, 6 July 2009 (UTC)

Britanica text

On the whole we, at CZ, see the Britanica as our role model. The Britanica gives the following for "work" (note its readability or lack thereof):

in physics, measure of energy transfer that occurs when an object is moved over a distance by an external force at least part of which is applied in the direction of the displacement. If the force is constant, work may be computed by multiplying the length of the path by the component of the force acting along the path. Work done on a body is accomplished not only by a displacement of the body as a whole from one place to another but also, for example, by compressing a gas, by rotating a shaft, and even by causing invisible motions of the particles within a body by an external magnetic force.

No work, as understood in this context, is done unless the object is displaced in some way and there is a component of the force along the path over which the object is moved. Holding a heavy object stationary does not transfer energy to it, because there is no displacement. Holding the end of a rope on which a heavy object is being swung around at constant speed in a circle does not transfer energy to the object, because the force is toward the centre of the circle at a right angle to the displacement. No work is done in either case.

The mathematical expression for work depends upon the particular circumstances. Work done in compressing a gas at constanttemperature may be expressed as the product of pressure times the change in volume. Work done by a torque in rotating a shaftmay be expressed as the product of the torque times the angular displacement.

Work done on a body is equal to the increase in the energy of the body, for work transfers energy to the body. If, however, the applied force is opposite to the motion of the object, the work is considered to be negative, implying that energy is taken from the object. The units in which work is expressed are the same as those for energy, for example, in the metre-kilogram-second system, joule (newton-metre); in the centimetre-gram-second system, erg (dyne-centimetre); and in the English system, foot-pound.

--Paul Wormer 06:33, 6 July 2009 (UTC)