Differences between two Voltage formulas

AI Thread Summary
The discussion highlights the differences between two voltage formulas: one for a point charge, V = k(q/r), and one for an inductor, V(t) = L(di/dt). Each formula applies to distinct physical scenarios, with the first relating to electrostatics and the second to electromagnetic induction. The conversation suggests that while both equations involve voltage, they represent different concepts and cannot be directly derived from one another. The relationship between these formulas can be understood through Maxwell's equations, which unify various electromagnetic phenomena. Ultimately, the context of voltage generation in each case is crucial for understanding their applications.
sawer
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What is the differences between these two voltage formulas.
1. for a point charge: $$V = k\frac{q}{r}$$
2. for an inductor: $$V(t)= L\frac{di}{dt}$$

Why are there different voltage formulas? Can second one be derived from the first one?
Or do they completely represent different concepts?
 
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The two expressions refer to different circumstances; sub-sets of the general case. If you look at Maxwell's equations then you will see how it all ties together.
It is common for equations describing phenomena to share a variable.
 
Can you please give some hints
 
Just think of the suvat set of equations used for calculations in dynamics. There is always a choice of how to express things in terms of different variables. Are you looking for some extra significance in this?
 
sawer said:
Can you please give some hints

Well, what is generating the voltage in each case?
 
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