Charge in a Circuit - Potential Energy Explained

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When connecting two points of different potentials in a circuit, charge flows due to the potential difference. Each unit of charge experiences potential energy influenced by its position relative to the lower potential point, but this is altered by the presence of resistive loads in the circuit. Charges lose potential energy as they traverse higher resistance loads, resulting in varying potentials even at equal distances from the lower energy point. The potential field in a conductor is not uniform like in free space, as the medium distorts the field. Understanding these dynamics is crucial for grasping how circuits operate.
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When we connect two points at different potentials in a cell with a conductor, we will have a circuit and charge will flow between the two points. Will each unit charge, just as if it were experiencing an electromagnetic force in free space, have a potential energy by virtue of its position from the point at lower potential it is attracted towards?

Each unit of charge will lose more of its potential energy (all of which it inevitably must lose if it is to reach the end of the circuit) in the loads with higher resistances. But this means that the charge can have different potentials at the same distance from the point at lower energy, depending on how much of the total resistance of the circuit it has gone through. Is there something I'm missing here? Does the force act somehow 'around the circuit', rather than straight?

Help is appreciated.
 
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Originally posted by speeding electron
Will each unit charge, just as if it were experiencing an electromagnetic force in free space, have a potential energy by virtue of its position from the point at lower potential it is attracted towards?
No, not just like in free space. It will not be in free space, but in a material that conducts, which is a very different situation. The cell has two poles. Why are you disregarding the other one?




Originally posted by speeding electron
Each unit of charge will lose more of its potential energy ... in the loads with higher resistances. But this means that the charge can have different potentials at the same distance from the point at lower energy, ...
That is because the potential field does not necessarily have the same symmetries in this case, as it would in free space. The presense of media (i.e. conductors) distorts the potential field.
 
OK, thanks for clearing that up. :wink:
 
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