Work: Definition & Explanation

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    Definition Work
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Discussion Overview

The discussion revolves around the definition and explanation of work in physics, exploring various interpretations and contexts in which work is understood. Participants examine the relationship between work, energy, and force, as well as the implications of different definitions in both theoretical and practical scenarios.

Discussion Character

  • Conceptual clarification
  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • One participant proposes that work done is the amount of energy exchanged in executing an action through a non-spontaneous method.
  • Another participant questions the meaning of "executing an action through non-spontaneous method."
  • A different participant suggests that the usual definition of work is "energy exchanged by any means other than heat," indicating a potential disagreement with the initial definition.
  • One participant emphasizes the equation W=Fd, arguing that if a force acts on a body, it imparts energy, whether potential or kinetic, or does work on the system.
  • Another participant provides an example involving a magnet and a charged particle to illustrate a spontaneous action and questions whether work is done in that scenario.
  • One participant clarifies that W=Fd should be interpreted as "acts for a distance" rather than "acts on a body," noting that work is not done if a force is applied without movement.
  • A participant suggests that the definition of work should specify work done 'on' an object versus work done 'by' an agency to avoid confusion regarding efficiency.
  • Another participant expresses a preference for the "energy transferred" definition, arguing it is more applicable in complex scenarios involving fields.

Areas of Agreement / Disagreement

Participants express differing views on the definition of work, with some agreeing on the importance of the equation W=Fd while others challenge the initial definition and its implications. The discussion remains unresolved with multiple competing interpretations of work.

Contextual Notes

Participants highlight the potential confusion arising from different definitions and contexts in which work is discussed, particularly regarding spontaneous versus non-spontaneous actions and the role of agency in defining work.

Tony Stark
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Can work be explained in following context-

Work done is the amount of energy exchanged in executing an action through non-spontaneous method.
 
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Tony Stark said:
executing an action through non-spontaneous method.

What does this mean?
 
Tony Stark said:
Work done is the amount of energy exchanged
This is good. The rest seems wrong. The usual definition is "energy exchanged by any means other than heat"
 
I think the equation W=Fd explains it all. If a force acts on a body, it gives it energy, potential or kinetic, or it does work to the system.
 
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Tony Stark said:
through non-spontaneous method.
Just to add, say you cover up a positively charged magnet with a thick material so that it can't affect a nearby negatively charged particle. For one millisecond, you uncover the magnet and the particle quickly accelerates towards the magnet. This is spontaneous, is it not? Was work done? Yes.
 
Isaac0427 said:
I think the equation W=Fd explains it all. If a force acts on a body, it gives it energy, potential or kinetic, or it does work to the system.
It's probably better to say "acts for a distance" instead of "acts on a body" (put a weight on a table and a force is acting on the table but no work is being done - unless the table breaks under the load)... But with said, yes W=Fd does pretty much say it all.
 
Isaac0427 said:
I think the equation W=Fd explains it all. If a force acts on a body, it gives it energy, potential or kinetic, or it does work to the system.
I think that it should be made clearer that this is the definition of work done 'on' an object and not the work done 'by' an agency. This would remove the possible confusion when efficiency is brought in. The 'agency' could be doing much more work than is being usefully provided to the object.
 
Nugatory said:
It's probably better to say "acts for a distance" instead of "acts on a body" (put a weight on a table and a force is acting on the table but no work is being done - unless the table breaks under the load)... But with said, yes W=Fd does pretty much say it all.
I prefer the "energy transferred" definition because it applies for fields too, and it helps me keep things straight in complicated scenarios.
 
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