What does lower voltage and higher voltage mean?

[Astra]

In my book it says that electrons travel from lower potential ( lower voltage) to a higher potential ( higher voltage). While protons travel from a higher potential to a lower potential.

I am confused as to what this means.

I understand the following:

Electric potential energy is the distance a certain charge is from the its opposite charge ( almost like gravitational potential energy)

Voltage is the electric potential energy per charge ( so if something has an electric potential energy of 6 J and its charge is 2 C, the voltage will be 3 V)

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[aldol16]

In my book it says that electrons travel from lower potential ( lower voltage) to a higher potential ( higher voltage). While protons travel from a higher potential to a lower potential.

You're confusing potential with voltage. Voltage is a potential difference and is measured between two points in space. Saying that one point in space has a "low voltage" makes no sense physically. It could have a low electric potential but not a low voltage because voltage is a comparison between two points. Kind of like a displacement. It doesn't make sense to say that an intrinsic "displacement" is associated with any one point in space because displacement is measured relatively.

The key equation to keep in mind here is: W = q*V, or the equation for work done by an electric field. In order for the electric field to do any work on a particle, the work must be negative. Otherwise, the particle would be doing work on the electric field. So W must be negative. Now, imagine you have an electron. For an electron, q = -1 times elementary charge. Therefore, to make W negative, V must be positive. Remember what I said above. V is the potential difference between two points in a field. So if V is positive, that means final potential must be higher than initial potential (V = final potential - initial potential). That means an electron will only flow (work done on it by the field) when it moves from somewhere with low potential to somewhere with high potential.

Now repeat the exercise for a proton.

From what you posted, it seems like you're confused about the difference between electric potential, which is expressed in units of volts, and voltage, which is a difference between two points also expressed in units of volts.

 

[sanrose]

Think about it this way:
Lower potential = negative electrode Higher potential = positive electrode.

Negative charges (i.e. electrons) move towards positive electrode (higher potential)
Positive charges (i.e. currents) move towards negative electrode (lower potential)

 

[Astra]

You're confusing potential with voltage. Voltage is a potential difference and is measured between two points in space. Saying that one point in space has a "low voltage" makes no sense physically. It could have a low electric potential but not a low voltage because voltage is a comparison between two points. Kind of like a displacement. It doesn't make sense to say that an intrinsic "displacement" is associated with any one point in space because displacement is measured relatively.

The key equation to keep in mind here is: W = q*V, or the equation for work done by an electric field. In order for the electric field to do any work on a particle, the work must be negative. Otherwise, the particle would be doing work on the electric field. So W must be negative. Now, imagine you have an electron. For an electron, q = -1 times elementary charge. Therefore, to make W negative, V must be positive. Remember what I said above. V is the potential difference between two points in a field. So if V is positive, that means final potential must be higher than initial potential (V = final potential - initial potential). That means an electron will only flow (work done on it by the field) when it moves from somewhere with low potential to somewhere with high potential.

Now repeat the exercise for a proton.

From what you posted, it seems like you're confused about the difference between electric potential, which is expressed in units of volts, and voltage, which is a difference between two points also expressed in units of volts.

This made so much sense. Thank you very much