Before getting into the topic, we have to keep two points in mind.1. Conventional Current flow. (The way Current is said to flow historically)
2. Actual current flow. (The way Current actually flows).
By definition, current is the flow of charges, basically electrons. It is said to flow from a point of higher potential to lower potential.
What is higher potential and lower potential?
Before the discovery of atomic structure, scientists believed that positive charge flow from a point where it is more to a point where it is less.The point where they said there are more positive charges and called it as higher potential.
The point where there are more negative charges or no charge is considered as lower potential.
Later after the exploration of atomic structure, scientists realized that it is electrons (negatively charged particles), that flows and the actual higher potential is the electron-rich negative.
So, if we consider a battery, decades ago it was believed that there are more positive charges at the positive terminal and it moves towards the flow of current. But now we know, negatively charged electrons move from the negative terminal are attracted by the positively charged ions at the positive terminal of the battery and move towards it.
Conclusion:
- The higher potential is the point of higher concentration of charges and lower potential is the point with a lesser concentration of charges.
- Historically scientists believed that the positive charge is the one that flows. Hence considered the point which is more positive as a higher potential point (Conventional current flow)
- Later, after the exploration of atomic structure, it was concluded that electrons that are negatively charged are the one that flows and hence the point which is more negative is considered higher potential (Actual current flow).
- But still, physicists say the direction of current flow is from positive point to the negative point and consider the positive point as the higher potential, while vice versa is the flow of electrons.
Hi!
I would like to pose a question here concerning High and Low potential with regard to Kirchhoff laws. Will working with Kirchhoff laws, applying the electron flow invalidate my circuit analysis /
Thanks.
Applying the electron flow will not invalidate your analysis. But, you need to consider electron flow in each loop.
hi! I was wondering how to apply this with a galvanic cell. Is it fair to say the cathode then is at higher potential? does this also apply to an electrochemical cell?
Yes, you can say so. Our conventions have taught us to say otherwise.
yes.. in the galvanic cell the cathod is the positive terminal…. and the anode is the negetive terminal….
bcz.. in the galvanic cell in the anode always oxidation is takes place.. it means always the loss of the electrons and the anode gets full by positive charge… and similarly in the cathode the reduction is takes place it means gain of electrons… it means the cathod is attract the electons towards it self… so that we say always the electrons flow from the anode to cathode and the current flow is from opposite to the flow of current then the current flow from cathode to anode and hence the current is flow from higher potential to lower potential so that the cathode is higher potential and the anode is the lower potential
i hope it will help you
thank you
So, which charge (nature) is concentrated at higher potential of the cell?
Negatively charged electrons.
So, the considered point here now is that higher potential is in the negative terminal of the battery and not the positive terminal? If so, why are some pictures still using the positive terminal as the highest potential?
That is because they are following conventional current flow.
Hi! I was wondering why is it that we follow the convection even though it is not applicable in real life?