Why is Work Defined as Force Times Displacement?

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Work is defined as the product of force and displacement (Work = Force x Displacement) because it quantifies the energy transferred when a force moves an object through a distance. This definition is fundamental and not arbitrary, as it reflects the relationship between force applied in a specific direction and the resulting energy change in a system. Various forms of work exist, such as pressure times volume change and torque times angle, illustrating the versatility of the concept across different physical contexts. The ability to convert work into other forms of energy, like heat, further emphasizes its significance in scientific applications. Overall, this definition serves as a crucial framework for understanding energy transfer in physics.
hasankamal007
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Its known that Work=Force X Displacement or F x S.
But why?
Why is only F x S equal to work?
Why not something else like Work=blah X blah could be true?
 
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As far as I understand it, its a fundamental definition so its not derived, its a definition. The force exerted on a physical system and the distance in the force direction are both proportional to the potential that physical system gains for exerting a force through some distance, i.e. potential for work, aka "energy". So this quantitative definition of work results in transfer of energy, our qualitative definition of work.

If my understanding is wrong, someone please do give me some constructive criticism.
 
Work / energy can take many forms, in fact.
It can be:
Pressure times volume change.
Torque times angle
Charge times Potential difference

You could say it's a definition but it's more than that. It's not just arbitrary because you can transfer work, defined one way, into work, defined another way and then into Heat (internal energy).

It's a quantity that Science has found useful to deal in.
 
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This has been discussed many times on PF, and will likely come up again, so the video might come handy. Previous threads: https://www.physicsforums.com/threads/is-a-treadmill-incline-just-a-marketing-gimmick.937725/ https://www.physicsforums.com/threads/work-done-running-on-an-inclined-treadmill.927825/ https://www.physicsforums.com/threads/how-do-we-calculate-the-energy-we-used-to-do-something.1052162/
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