# Volts vs voltage

As I have understood it voltage is electric potential difference while volts are just electric potential. So I can say that the negative end (ground) of a battery has many volts since there's a lot of negative charge packed together and that causes electric potential. But at the same time the negative end also has 0 voltage because its used as ground which is the reference point in a circuit.

Have I understood this correctly or am I making no sense?

• "Have I understood this correctly or am I making no sense?" - more the latter :)
– Rev
Jul 30 '15 at 6:39

Voltage is a difference of electric potential. To simplify, it is an measure of the difference in concentration of electrons between two points.

Volts is a unit of measure of voltage.

It would be pretty difficult to have exactly no electron on an electrode, and as the voltage is the difference of potential, it is always relative to somthing. Usually, we say that a given electrode has $X$ volts and that implied relative to the ground of the circuit. The voltage of the ground is 0 volts, because it is referenced to itself. However, if you measure the voltage of a ground in one circuit, as a reference of another ground in another circuit, you may see some difference (non-zero).

• But then what do we use to measure electric potential? What if I for example want to express how much potential an electron sitting right next to another electron has? Jul 30 '15 at 7:01
• @JustsomeGuy you measure the voltage against a known reference. Jul 30 '15 at 7:04
• Can't we measure the electric potential energy of an object in the same way we can measure the gravitational potential energy of an object? Why does it always have to be between two points? Jul 30 '15 at 7:12
• Isn't "difference in concentration of electrons" a bit of a stretch? Jul 30 '15 at 9:10
• @Justsomeguy, you could, from the electric field generated. This is explained in the Wikipedia article. However it is not very practical. Jul 30 '15 at 9:13

Voltage is electric potential difference between any two points in the circuit.

Volts are units which describes that electric potential difference between two points in the circuit.

Let's ignore the terms voltage and volts for now and get an understanding first.

Imagine I had a frozen chicken of mass 1kg hurtling down from 1km above the earth's surface. For now we can approximate g=9.81 and get to work. At its initial height of 1km, the chicken has a potential energy of mgh=9810J. In other words, as the chicken plummets from the sky, it will gain a kinetic energy of 9810J (engineers do not know of air resistance). Now lets say we had a lot of chickens we wanted to drop from the sky, we need a better unit.

So I bring to you, the Poult. The Poult (P) is the energy gained by a chicken as it falls from one point to another. This makes it simple, now the point 1km above the ground is 9810P higher than the surface of the earth. Any chicken falling through this height will gain energy of 9810J. We can say that the poultage of the point 1km above the surface is 9810P.

So now circuits. It's basically exactly the same thing. The volts are the amount of energy a coulomb worth of electrons will release as they travel from one point to another. We can say that the volts at a certain point are 0V just as we can say that the poults on the ground are 0P. It may not scientifically be 100% correct, but as engineers, that's not a concern. Instead setting the surface to 0P gives us a convenient way to define the poultage at all the points above the earth. Same for circuits.

Hope this helps.

For all the people ending up here looking for the difference between the words volt and voltage.

To use "Length" as an analogy.

Voltage corresponds to length. Volt(s) corresponds to meters (or feet for our imperial friends).

"the voltage is 24 volts" "the length is 10 meters" "the current is 2 ampere"

writing millivoltage is like writing millilength. voltage is synonymous to "electric potential"

• So, 1 meter is the same as 1 lenghtage, right?
– RJR
Jun 8 '20 at 14:48