Is it intuitively correct to think of voltage as a “propellant” force?

Question

From my understanding

1. voltage is an electromagnetic force that creates current by exerting a force on an atom that causes that atom to transfer one of its valence electrons to the neighboring atom. The atom that lost a valence electron becomes a positively charged ion and then “steals” a valence electron from the succeeding atom to restore charge balance. This effect propagates throughout the circuit.
2. Voltage and current are directly related. the larger the voltage/emf, the faster one atom’s valence electron jumps to the next = larger current/electron propagation

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Assuming this is in essence all accurate: say we have a simple series circuit with a 5V supply and 2 equal resistors.

The voltage drops throughout the circuit from 5 -> 0, but as we know current is the same across a series circuit

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So intuitively, Speaking about series circuits only, is it valid to think of voltage as a “propellant” force or only as a force that “gets the electrons moving” initially and depending on the amount of force, sets the speed at which they “move.”

As an example of this, if we have a person who slingshots a rock in space (space so that the velocity of the rock is constant), voltage would be the force exerted on the rock initially that determines how fast the rock moves through space but after the rock left the slingshots pouch, that force would have no effect on the rock after that point.

Or is voltage more of a “driving force”?

An example of what I mean, if we have a person who’s pushing a boulder on a flat plane, voltage would be the force that’s exerted on the boulder. If the person stopped pushing, the boulder/electrons would stop moving/propagating.

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I ask this because voltage drops across the circuit From 5v to 0v but current remains the same, so it seems as if voltage’s only responsibility is to start and set the speed of the current in the beginning of the circuit, but after that current acts independently of that voltage.

Answer 1

It would be incorrect to think of voltage as a propellant, propellants accelerate and most of the time diffuse. Propellants are gasses most of the time.

It is correct to think of voltage as a pressure and electrons as a fluid. Voltage sources are like pumps. Current is like flow. Resistors are like restrictions. That is the best physical analogy of a circuit.

Answer 2

Electromotive Force May be the term you seek

https://en.m.wikipedia.org/wiki/Electromotive_force

Answer 3

Driving force is more accurate, there's no real inertia to the elections so to keep them moving there always has to be something down the line that's pushing. Like you said there's the valence electrons shifting which drives the electrons at the end of the circuit to all keep moving onward. The more voltage potential, the bigger the obstacles the little electrons can overcome!!

Regarding the relationship between current and voltage, it sounds like you have a chicken-or-the-egg issue with your understanding. Current is a physical property where a circuit will have a defined number of electrons flowing through it per second (Amps = Coulombs/second). Based on the constant current flow through the circuit, each node between resistances will end up at a certain voltage.

For example, if you have two different batteries and attach them to an arbitrary circuit, the higher voltage battery will push harder and drive more electrons through the circuit. Using the current as a starting point, we can then calculate the voltage drop over each resistor and determine the node voltages.

Circuit analysis starts with looking at the circuit from the perspective of the voltage source, and then working out from there. In the circuit below the 12V source has no idea how many resistors there are and it doesn't care, all it sees is that it has to push eletrons through 12\$\Omega\$ of stuff to get the electrons to go through. Using Ohm's Law the current will be \$I=\frac{V}{R}\$ so I = 12/12 = 1A.

Since we know there will be 1A flowing through each resistor we can find that for each resistor a 1A current will cause a 4V drop across each one because of Ohm's Law: \$V=I*R\$ so V = 1*4 = 4V.

Intuitively this makes sense because each resistor is the same so the voltage will be evenly distributed through the circuit, using those same steps you can analyze any resistor circuit as long as you know how to calculate equivalent resistance for parallel and series combinations of resistors.

^{simulate this circuit – Schematic created using CircuitLab}