Differences between two Voltage formulas

[sawer]

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?

 

[sophiecentaur]

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.

 

[sawer]

Can you please give some hints

 

[sophiecentaur]

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?

 

[Drakkith]

Can you please give some hints

Well, what is generating the voltage in each case?