Why we use the conventional direction for current flowing?

[Akash47]

I often get confused that why we have to use the ancient idea for the direction of current flowing.I have come to know a very weak reason for it.It is said that when current was first discovered,it was assumed that the current flows from the positive region to the negative region(using the idea of static electricity).But now,we know that the real direction of flowing electricity is opposite to the conventional one.So is there any other strong reason for choosing this ancient assumption and does it effect for choosing this wrong direction?

 

[Nugatory]

Imagine the implications of changing the convention... Say we change it effective 1 Jan 2019...

I'm replacing the battery in my car. If the replacement battery was manufactured before switchover day, I connect the battery terminal marked "+" to the positive cable in my car's wiring harness (likely also marked "+") and the one marked "-" to the ground cable. If the battery was manufactured after switchover day, I have to do it the other way around - and if I get it wrong I may fry the car's engine computer and other electronics.

Now multiply this by many billions of polarity-sensitive machines, measuring instruments, electronic devices, batteries, power supplies across the world. The disruption is a very strong reason for not changing the convention we use.

 

[nsaspook]

Conventional current is used with circuit theory with circuit analysis ports. This provides a mathematical proven convention to calculate energy flows from one element to another in a circuit.
https://en.wikipedia.org/wiki/Port_(circuit_theory)

Using electron flow instead will also work but then you need to flip signs (flow of positive charge) to keep the calculations consistent with defined physics terms.

 

[ZapperZ]

I often get confused that why we have to use the ancient idea for the direction of current flowing.I have come to know a very weak reason for it.It is said that when current was first discovered,it was assumed that the current flows from the positive region to the negative region(using the idea of static electricity).But now,we know that the real direction of flowing electricity is opposite to the conventional one.So is there any other strong reason for choosing this ancient assumption and does it effect for choosing this wrong direction?

In addition to what has already been said, it also happens that we DO have instances where positive charges flow. Holes in semiconductors, positive ions and protons in particle accelerators, etc... are all "conventional currents". They all follow what we have already designated by convention.

At some point, you need to evaluate whether changing convention actually produces something of real benefit, or if it is simply to placate someone based on a matter of personal preference.

Zz.

 

[Nugatory]

I've posted this from time to time in the past (and it was another PF member who first told me about it) but reposting is easier than digging up the old posts...
https://xkcd.com/567/

 

[nsaspook]

I've posted this from time to time in the past (and it was another PF member who first told me about it) but reposting is easier than digging up the old posts...
https://xkcd.com/567/

That a great cartoon and it's great because the opposite is usually true. It's usually electrical engineers that try to inform a electrical novice that the physical direction of charge flow is NOT an important factor of electrical energy transfer in the vast majority of circuits. What's important is how charge becomes separated and the potentials (The electric field) that occur from that separation.

https://www.physicsclassroom.com/class/circuits/Lesson-2/Electric-Current

So the guy doesn't really care about the direction of current in the cartoon, he wants to change history and stop having to explain why it doesn't matter.

 

[RPinPA]

I've posted this from time to time in the past (and it was another PF member who first told me about it) but reposting is easier than digging up the old posts...
https://xkcd.com/567/

There's an XKCD for everything! I was going to mention old Ben. Franklin's work established that there were two opposite flavors of "electric fluid", so he made an arbitrary choice of which one to call positive and which one to call negative. It turns out that in our universe electrical effects are mostly due to electrons, which happen to be the ones he assigned a negative value. The direction of conventional current is connected to which one is called positive, as the XKCD comic says more pithily.

To the OP: although electrons are what flow in most of our wires, you can certainly have current consisting of positive particles. Most of the currents that make up nerve signals inside your body for instance are composed of positive sodium ions. And flow of "holes" as mentioned by an earlier answer is important to how solid-state electronics work.

When a current of anything is flowing, the direction of current is the direction where more of that stuff is piling up. If you have a water current, you're getting more water at the end of the current and less at the beginning.

When you have a current of charge, you're getting more charge (more positive) at the end the current is flowing toward, and less at the other end. The fact that this is happening in many of our circuits by removing negative charges at the downstream end is irrelevant.