Confused about Current Flow & Capacitances

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SUMMARY

This discussion clarifies the concept of current flow and capacitance, specifically in the context of electrochemical cells and batteries. It establishes that electrons, which carry a negative charge, flow from the negative terminal (low potential) to the positive terminal (high potential), contrary to conventional current flow which is described as moving from positive to negative. The confusion arises from historical sign conventions that label electron flow as "uphill" despite the physical movement being from low to high potential energy states. The discussion emphasizes the importance of understanding these conventions for accurate interpretation of electrical circuits.

PREREQUISITES
  • Understanding of electrochemical cells and their function
  • Familiarity with electrical potential difference and current flow
  • Knowledge of charge carriers, specifically electrons
  • Basic principles of battery operation and chemical reactions
NEXT STEPS
  • Research the principles of electrochemical cell operation
  • Learn about the implications of sign conventions in electrical engineering
  • Study the relationship between potential energy and current flow in circuits
  • Explore the chemical reactions occurring in batteries and their effect on charge separation
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Students and professionals in electrical engineering, physics enthusiasts, and anyone seeking to deepen their understanding of current flow and capacitance in electrochemical systems.

D_DaYwAlKeR
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I have some doubts regarding Current Flow and Capacitances...

I Read this somewhere..
" an electrochemical cell supplies energy to move a charge from its low energy, low potential terminal to the high energy, high potential terminal. In this sense, the cell supplies the energy to establish an electric potential difference across the two ends of the external circuit. Charge will then flow through the external circuit in the same manner that water will flow from an elevated position to a low position. It is the difference in potential that causes this flow..."


it says that charge (electron) will travel from Low potential to high potential...
then its says that it will move in the same manner that water will flow from an elevated position to a low position..( high potential to low potential...) ..i didnt get this at all..!
 
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D_DaYwAlKeR said:
it says that charge (electron) will travel from Low potential to high potential...
then its says that it will move in the same manner that water will flow from an elevated position to a low position..( high potential to low potential...) ..i didnt get this at all..!

It's just a matter of a sign convention, because electrons are said to have negative charge. Life would be a lot easier if a century and a half ago we had decided to call the electron's charge "positive" instead of "negative" so that they would naturally move from areas of high "positive" charge to low "positive" charge - but back then we didn't know which direction the physical charge carriers were moving, and arbitrarily chose a sign convention that turns out to be inconvenient for talking about electrons.

To this day we take power from the positive terminal of a battery, and talk about the wiring diagram as if electrical current is flowing "downhill" from the positive terminal; but what's actually happening physically is that electrons are flowing "uphill" from the negative terminal.
 
I got it nw...

Electron loses potential energy as it moves from low potential to high potenital..!...thnxx...@Nugatory!
 
I believe the beginning they are talking about a chemical battery; it talks about moving the charge from a low energy state to a high energy state.

In a battery, a chemical reaction supplies the energy to separate the charges between the cathode and anode, which causes an electrical potential difference across the terminals and puts the charges into a high potential energy state. When the terminals are connected by a conductor, the stored energy is releases as current. And as Nugatory said, the convention is to label the current as flowing from positive to negative.
 

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