What is the role of the electric field in a battery?

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Discussion Overview

The discussion revolves around the role of the electric field in a battery and its influence on the flow of charge within a circuit. Participants explore the relationship between electric fields, voltage, and current flow, particularly in the context of how electrons move in response to the electric field established by the battery.

Discussion Character

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

Main Points Raised

  • Some participants assert that the electric field created by the battery influences the movement of charges, questioning whether the electric field does work on the charges or if they move against the field.
  • One participant notes that electrons, being negatively charged, move against the direction of the electric field lines, which leads to a discussion on the nature of current flow in metallic wires.
  • There is a reference to a resource stating that the electric field set up in a wire causes current to flow when there is a complete circuit, prompting questions about the direction of the electric field and its effect on charge movement.
  • Participants discuss how the presence of a conductor alters the electric field lines, suggesting that the field lines run through the wire and contribute to the behavior of the circuit.
  • One participant expresses confusion about whether charge flows in the direction of the electric field, seeking clarification on this point.
  • Another participant emphasizes that the electric field indicates the direction of force on positive charges, while electrons move in the opposite direction, reinforcing the concept of conventional current versus electron flow.

Areas of Agreement / Disagreement

Participants express differing views on the relationship between the electric field and charge movement, with some agreeing that electrons move against the electric field while others seek further clarification. The discussion remains unresolved regarding the implications of the electric field on charge flow.

Contextual Notes

There are limitations in the discussion regarding the assumptions made about the behavior of electric fields in conductors and the interpretation of current flow. The relationship between electric fields, voltage, and charge movement is not fully settled, and participants reference different models and explanations.

user111_23
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I know that the battery creates an electric field around a conductor connected to it, but does this E-field actually do work on the charge, or do the charges go against the field?

I am treating current as the flow of electrons from negative to positive.
 
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Electrons go against the electric field lines (note that work that occurs naturally is from higher potential energy to lower potential energy; a negative potential energy denotes bounded systems, while energy is a scalar measure). Also take note that an electric field does flow through a conductor (the field lines are altered by the conductor).
 
Thanks for the reply.

I asked this question because of what this resource said:

"The battery provides a voltage (V) between its terminals. The electric field set up in a wire connected to the battery terminals causes the current to flow, which occurs when the current has a complete conducting path from one terminal of the batter to the other—called a circuit."

But look at this picture:

454px-Electric_dipole_field_lines.svg.png


If the electric field points in such directions, then how does the field push the charges to the positive terminal?
 
user111_23 said:
Thanks for the reply.

I asked this question because of what this resource said:

"The battery provides a voltage (V) between its terminals. The electric field set up in a wire connected to the battery terminals causes the current to flow, which occurs when the current has a complete conducting path from one terminal of the batter to the other—called a circuit."

But look at this picture:

454px-Electric_dipole_field_lines.svg.png


If the electric field points in such directions, then how does the field push the charges to the positive terminal?

Those are field lines in a vacuum. The field lines are altered when you put in other objects; so with a conducting wire-circuit, the field lines are actually running through the wire (part of what makes a good conductor a good conductor). The more general Ohm's Law (better viewed quantum mechanically) takes this into account.
 
Gear300 said:
Those are field lines in a vacuum. The field lines are altered when you put in other objects; so with a conducting wire-circuit, the field lines are actually running through the wire (part of what makes a good conductor a good conductor). The more general Ohm's Law (better viewed quantum mechanically) takes this into account.

I see. So I'm guessing that charge does not, in fact, flow in the direction of the electric field. Correct?

Thanks for the help!
 
user111_23 said:
If the electric field points in such directions, then how does the field push the charges to the positive terminal?

The charges which are free to move in metallic wires are electrons. A current in a metallic wire is therefore a flow of electrons.

The lines of an electric field show the direction of such field at any point in space, and therefore the direction of the corresponding force that would act on a free positive charge put in such point.

Electrons are negative charges. Hence they go to the opposite direction, "against" the direction of the E field in the picture, i.e. they go from "-" to "+" as you would expect from the old "charges of equal sign repel each other".

You should treat current as the flow of positive charge per time unit:

I = dQ/dt
 

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