Can Newton's Second Law be Derived from the Work Energy Theorem?

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SUMMARY

The discussion centers on the derivation of Newton's Second Law (F=ma) from the Work-Energy Theorem (W=1/2mv²). The user explores the relationship between these two fundamental concepts in physics, utilizing differential calculus to express force in terms of work done. The consensus is that while both formulations are equivalent, F=ma is often viewed as more fundamental due to its direct relation to observable phenomena like force and acceleration, compared to the more abstract nature of work and energy.

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  • Understanding of Newton's Second Law (F=ma)
  • Familiarity with the Work-Energy Theorem (W=1/2mv²)
  • Basic knowledge of differential calculus
  • Concept of force as a vector quantity
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  • Study the derivation of the Work-Energy Theorem in detail
  • Learn about the applications of Newton's Laws in real-world scenarios
  • Explore advanced topics in vector calculus relevant to physics
  • Investigate the philosophical implications of different formulations of physical laws
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Students of physics, educators teaching classical mechanics, and anyone interested in the foundational principles of motion and energy in the physical sciences.

namanjain
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i was just thinking over line that my teacher told - "Newton's second law is ultimate truth"
i feel why one can say 'F=ma' is more prestigious th 'work energy method' Though i know they are one and same thing, i was planning to derive (using principle of reverse engineering) second law of Newton from work energy theorem.
Just help me out tellin' if my method is correct [i donno high-fi vector calculus (not even much of basics)]

W= 1/2mv2
differential form

(dW)=(m)(v)(dv)

F.dx = mvdv
F = mvdv/dx
F = m(dv/dt)
 
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namanjain said:
i was just thinking over line that my teacher told - "Newton's second law is ultimate truth"
To some extent that's an aesthetic judgement, so there's no particular reason why you and your teacher have to agree about whether ##F=ma## or ##W=fd=(mv^2)/2## is more fundamental. However, forces and accelerations are things that we can see and feel, whereas work and energy are more mathematical abstractions that we constructed after the fact to help us explain the workings of force and acceleration. Thus, you'll probably find that many people share your teacher's sense of "ultimate truth".

There's nothing wrong with your reverse-engineering exercise - indeed, it pretty much has to come out that way if the theory is consistent (and I presume you and your teacher agree about that).
 

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