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Comment by hackits | Hacker News Reader

One thing that took me a long time to `get` was the concept of voltage is a bit miss-leading if you look up the definition even in the video of (http://afrotechmods.com/tutorials/2016/10/03/basic-electrici...).

Everyone wants to talk about the penitential energy and what-not. Though that is mostly pointless unless you grasp the first fundamental concept of voltage. Voltage is just simply the effort exerted by electromagnetic field on neighboring electrons.

As soon as you grasp that all definition of voltage relate to the real world of doing `work` eg... heating, moving then the concept of voltage of amps is a lot easier to understand.

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> Voltage is just simply the effort exerted by electromagnetic field on neighboring electrons.

That sounds like you are talking about the _electric field_, which is a vector field. Charged particles feel a force in the direction that the electric field is pointing. This is analogous to the gravitational force field (a vector field pointing towards the ground) and how objects with mass feel a force in this direction.

The electric field has a _potential_ [0] (called the _electric potential_), which is a scalar field. This is analogous to gravitational potential, which coincides with height.

_Voltage_ is the difference between the electric potentials of two points, for example the two leads of a resistor (or other circuit element).

[0] https://en.wikipedia.org/wiki/Scalar_potential

I think there is a caveat here:

force on electrons is "EMF", https://en.wikipedia.org/wiki/Electromotive_force

This scan be measure in volts, or joules.

"potential difference" seems to be the relative difference between the "EMF" of two conductors, which is analogous to pressure-difference and is the relevant factor wrt current, power, etc.

Cheers Chris, cleared up the issue I had with potential difference didn't see it that way.

I was taught to think of voltage as a level or “elevation” of sorts. Ie the difference between two charges in relation to one another.

I was taught the same, though I never liked the concept of elevation, water, ect... It easier for me to quantify it when it relates to the real world such as newton force or doing work. The other reason I never really liked the concept of elevation it means nothing if you dont have gravity that is constantly acting on a object.

The other reason I never really liked the concept of elevation it means nothing if you dont have gravity that is constantly acting on a object

It's an analogy. That's how analogies work. I was hoping for some substantive reasons the analogy doesn't hold.

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