Electron flow through basic circuit element

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SUMMARY

The discussion centers on the flow of electrons in a basic circuit element, specifically analyzing two situations with different voltage and current values. In Situation A, with a voltage of 40V and a current of -10A, electrons are confirmed to be entering terminal 2, despite the conventional current direction suggesting otherwise. In Situation B, with a voltage of -60V and the same current, the conclusion remains consistent: electrons are entering terminal 2. The participants clarify that the conventional flow notation and passive sign convention dictate the interpretation of current flow in relation to voltage sources.

PREREQUISITES
  • Understanding of basic circuit theory
  • Familiarity with conventional current flow and electron flow
  • Knowledge of voltage and current relationships in circuits
  • Ability to interpret circuit diagrams
NEXT STEPS
  • Study the principles of conventional current vs. electron flow in circuits
  • Learn about the passive sign convention in electrical engineering
  • Explore the implications of voltage polarity on current direction
  • Review basic circuit analysis techniques using Kirchhoff's laws
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Electrical engineering students, educators teaching circuit theory, and anyone seeking to deepen their understanding of electron flow and current direction in electrical circuits.

Weird Fishes
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Homework Statement


Given that the current flow is due to electron flow, state whether electrons are entering or leaving terminal 2.
Code:
   i   _____
  -->  |   |
- -----|1  |
v      |   |
+ -----|2  |
       |___|

Situation A: V=40V, i=-10A
Situation B: V=-60V, i=-10A


Homework Equations


none.


The Attempt at a Solution


My thinking was this:
Code:
  -10  _____
  -->  |   |
- -----|1  |
40     |   |
+ -----|2  |
       |___|
would be the equivalent of:
Code:
  10   _____
  <--  |   |
- -----|1  |
40     |   |
+ -----|2  |
       |___|

meaning that current would be entering 2, and since we have defined current to be positive in the direction opposite the actual flow of electrons that electrons would be leaving 2. The solution doesn't elaborate, but it says that electrons are entering 2.

B:
Code:
  -10  _____
  -->  |   |
- -----|1  |
-60    |   |
+ -----|2  |
       |___|
would be the equivalent of:
Code:
  10   _____
  <--  |   |
+ -----|1  |
60     |   |
- -----|2  |
       |___|

meaning the same scenario as A, with the exception of voltage polarity. I was under the assumption that the flow of current defined the flow of electrons.
(using conventional flow notation and the passive sign convention)

All in all, I'm just looking for a correction of my logic. I doubt the solutions given are wrong, but I suppose it is possible.

Thanks in advance.
 
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Your solutions are correct.
 
I feel that the current direction shown is with respect to the voltage source positive terminal and not through node 1. In this way, the solution given in the book may be correct. Any ways, your way of thinking and your solutions are also correct.
 

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