Current Discrepancy: Why Positive Charge?

  • Thread starter Thread starter Opario
  • Start date Start date
  • Tags Tags
    Current
Click For Summary
SUMMARY

The discussion centers on the convention of defining electric current as the movement of positive charge, despite the actual movement being that of negative electrons. Participants highlight the historical context of this decision, noting that it was made before the discovery of electrons. The conversation also touches on the magnetic poles, questioning the terminology used in physics. Ultimately, the preference for thinking in terms of positive charge movement is acknowledged as a practical approach for understanding circuit behavior, especially in the context of solid state physics.

PREREQUISITES
  • Understanding of basic electrical concepts, including current and charge.
  • Familiarity with solid state physics principles.
  • Knowledge of circuit analysis and measurement tools like voltmeters and ammeters.
  • Awareness of magnetic field concepts and compass behavior.
NEXT STEPS
  • Research the historical development of electrical charge conventions in physics.
  • Explore solid state physics topics, particularly electron behavior in semiconductors.
  • Learn about circuit analysis techniques, focusing on the implications of charge movement direction.
  • Investigate the properties and behavior of magnetic poles and their terminology in physics.
USEFUL FOR

Students of physics, electrical engineers, and anyone interested in the foundational concepts of electricity and magnetism.

Opario
Messages
6
Reaction score
0
Why would it be an advantage to say that the direction of current in a wire is the "movement" of positive charge, when in fact it is the negative charge on electrons which is moving. And who decided to make that the universal rule, anyway?

And another thing: Isn't the north pole of the Earth really the south pole?
 
Engineering news on Phys.org
Opario said:
Why would it be an advantage to say that the direction of current in a wire is the "movement" of positive charge, when in fact it is the negative charge on electrons which is moving. And who decided to make that the universal rule, anyway?

Back before electrons were discovered, they had to make an assumption... 50% chance of being right...

Opario said:
And another thing: Isn't the north pole of the Earth really the south pole?

As I recall, the "N" end of a compass needle is termed the "North Seeking" pole.

Since the magnetic poles flip with monotonous regularity, if you hang around long enough the "N" of the compass needle will become the "South Seeking" pole... :biggrin:
 
Opario said:
Why would it be an advantage to say that the direction of current in a wire is the "movement" of positive charge, when in fact it is the negative charge on electrons which is moving.
I just find it easier to think about the direction positive charges would move in a circuit, rather than thinking about negative charge motion and continually reminding myself that the voltmeter or ammeter readings need a sign change.
 
Redbelly98 said:
I just find it easier to think about the direction positive charges would move in a circuit, rather than thinking about negative charge motion and continually reminding myself that the voltmeter or ammeter readings need a sign change.

After you start taking your first solid state physics class, you will probably think more in terms of electron movement. It's physically what's going on, after all, and it turns out not to be very hard to make the mental flip to "positive" current direction.
 
berkeman said:
After you start taking your first solid state physics class, you will probably think more in terms of electron movement. It's physically what's going on, after all, and it turns out not to be very hard to make the mental flip to "positive" current direction.

In that situation, yes you're absolutely right. It all depends on what you are working on. My first (and only) solid state physics class was about 25 years ago. These days I often work with circuits and meter readings.

When I look at what's going on in diodes and transistors I switch back to the electron point of view, it's easier in terms of understanding the physics as you point out.

Regards,

Mark
 

Similar threads

Replies
3
Views
2K
  • · Replies 5 ·
Replies
5
Views
3K
  • · Replies 6 ·
Replies
6
Views
6K
  • · Replies 12 ·
Replies
12
Views
3K
Replies
2
Views
2K
  • · Replies 5 ·
Replies
5
Views
2K
  • · Replies 3 ·
Replies
3
Views
3K
  • · Replies 4 ·
Replies
4
Views
1K
Replies
1
Views
1K
Replies
8
Views
2K