Does electricity passing through resistance decrease potential?

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    Potential Resistance
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Discussion Overview

The discussion revolves around whether the electric potential decreases when electric current passes through a resistance. Participants explore various aspects of this concept, including the nature of potential difference, energy dissipation in resistors, and analogies to physical systems.

Discussion Character

  • Exploratory
  • Debate/contested
  • Technical explanation
  • Conceptual clarification

Main Points Raised

  • Some participants suggest that the potential generally decreases as current flows through a resistance, but the specifics depend on how the potential is initially created.
  • One participant argues that current flows from higher potential to lower potential, indicating that potential decreases after passing through resistance, while also noting a discrepancy in textbook conventions regarding current direction.
  • Another participant mentions that charges dissipate energy as they pass through a resistor, leading to a loss of electrical potential, and describes the process using an analogy of water wheels losing gravitational potential energy.
  • There is a discussion about the limitations of analogies, with one participant questioning whether potential remains equal at equal heights regardless of the presence of resistors.
  • Another participant emphasizes that without resistors, charges would convert potential energy into kinetic energy, suggesting that potential would still drop along the way.

Areas of Agreement / Disagreement

Participants express differing views on the relationship between electric potential and resistance, with no consensus reached on the exact nature of this relationship or the implications of various analogies used.

Contextual Notes

Participants highlight the importance of terminology and the context in which potential is discussed, indicating that assumptions about potential differences and energy dissipation may vary based on the specific scenario being considered.

DriggyBoy
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Does the potential decrease when it charges(electricity) pass through a resistance?
Newbie here...please help :)
 
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Generally, yes, but much depends on how the potential is created in the first place. You may want to describe the situation that you have in mind.
 
No actually, current flows from higher potential to lower potential...so when the current reaches the resistance it is at a higher potential & whn it leaves, potential decreases...
Now in the book the dirn of current is considered oppo...that is from lower to higher potential...in this case potential increases after charges pass thru the resistance...
***
Am I right?
 
I misunderstood your question and did not, myself, use correct terminology.

When charges are moved by a potential difference, the potential difference generally decreases in magnitude.

The potentials in a potential difference can become lower or greater in this process.
 
DriggyBoy said:
Does the potential decrease when it charges(electricity) pass through a resistance?
Newbie here...please help :)

Energy will always end up somewhere and you don't get any from nowhere. The charges are dissipating energy as they go through a resistor (a resistor will get hot, if enough power is dissipated). That energy comes from the lost electrical potential as they move through the circuit. Charges that 'creep into' the negative terminal of the battery have none left (using the convention that the negative terminal is at Zero Potential.) The battery (generator) gives new charges, coming from the positive terminal, more potential.

Be careful using water analogies but you could look at the situation in a chain of resistors as being like a series of water wheels, down a hill, fed with water at the top, with the full gravitational potential energy. Each water wheel takes its share of the gravitational potential energy and the water emerging from the bottom wheel flows very slowly out into the drain, having lost its potential energy in stages.
 
sophiecentaur said:
Be careful using water analogies but you could look at the situation in a chain of resistors as being like a series of water wheels, down a hill, fed with water at the top, with the full gravitational potential energy. Each water wheel takes its share of the gravitational potential energy and the water emerging from the bottom wheel flows very slowly out into the drain, having lost its potential energy in stages.
But the potential is equal at equal heights whether the wheels are there or not, right?
 
ElmorshedyDr said:
But the potential is equal at equal heights whether the wheels are there or not, right?


Potential energy would be mgh. Without the wheels to take the energy off, the falling water would go faster and faster ( kinetic energy) and the analogy falls down. The charges / resistors are like the water / wheels. Without the resistors - say you had electrons through a vacuum, they would acquire all the Potential Enery as Kinetic. A different situation but, if course, Potential would still drop on the way.
Electrical Energy is QV.
 

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