Understanding the Relationship Between Force and Potential: Proving F = -dv/dx

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The relationship F = -dV/dx describes how force relates to the change in potential energy per distance, with V representing electric potential difference. The electric field E can be expressed as E = -dΦ/dx, leading to the conclusion that force F equals -q(dΦ/dx) or F = -dV/dx when considering charge q. In three dimensions, this relationship is generalized using the gradient operator. The discussion also touches on the interpretation of potential in quantum mechanics, questioning the implications of a particle having V=0. Understanding potential in this context raises questions about a particle's behavior and whether it implies perpetual motion.
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how can we prove this relation F= -dv/dx
could some one explain what we mean by the force equal to the change it potential per distance and
 
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sciboudy said:
how can we prove this relation F= -dv/dx
could some one explain what we mean by the force equal to the change it potential per distance and

Your question is ambiguously presented, because it appears as if "v" is velocity, rather than "V" as in electrical potential difference.

You should know that the electric field E is E = -d\Phi /dx in 1-dimension. Since F=qE, then F=qE= -q d\Phi /dx, where \Phi is the electrostatic potential. But q \Phi is V, the potential difference. Thus, F=- dV/dx.

In 3D, the derivative in 1D is replaced by the grad operator.

Zz.
 
If you accept that energy (work done) is basically Force x distance then:
Force x distance = change in energy
F x dx = dE so F = dE/dx
 
OK thank you sir ZApperz and thank you truesearch
now i have another question based in the meaning of potential in the quantum mechanics
what is the potential for example whe i say a particle have V=0 ? is that mean the particle will never stop any time ?? or what
 
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