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erocored
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As I understand potential difference is the reason of current. Does it mean that the electrostatic force creates current?
As @kuruman said, in an ordinary conductor, yes. However, that is a very large limitation. Many materials are not conductors and you can very easily have currents without potential differences and potential differences without currents in other materials. So you should not think of that as a general rule, just as a description of the behavior of conductors.erocored said:As I understand potential difference is the reason of current. Does it mean that the electrostatic force creates current?
If a conducting wire is left alone, there is no current. If a potential difference is established across its ends with a battery, there is a current. Arguably, the electrostatic potential difference and hence the electric force derived from it cause the charge carriers to flow from one end to the other. With that understanding, I think it is safe to say that the electrostatic force "creates" the current. That's what I thought OP's initial query was about.Dale said:Also, if you have a current source then, even in a conductor you could consider the current to be creating the potential difference instead of the other way around. A conductor merely establishes a relationship between current and potential difference, it does not imply causality.
If a conducting wire is left alone, there is no voltage. If a current is established through the wire with a transistor, there is a voltage.kuruman said:If a conducting wire is left alone, there is no current. If a potential difference is established across its ends with a battery, there is a current.
Arguably the charge carriers flowing from one end to the other and the electric force derived from it cause the electrostatic potential difference.kuruman said:Arguably, the electrostatic potential difference and hence the electric force derived from it cause the charge carriers to flow from one end to the other.
With that understanding, I think it is not safe to say in general that either creates the other.kuruman said:With that understanding, I think it is safe to say that the electrostatic force "creates" the current.
Yes, of course. I didn't think of current sources even though I have used them. Count me as one of these people.Dale said:People tend to think in terms of voltage causing current because their most familiar sources are voltage sources (batteries and household power). But current sources do exist and are equally valid sources.
It depends what you mean by a 'circuit'. Charges can build up on a part of a conducting objet when charged particles arrive from elsewhere and they will flow through the conductor until the potential is a minimum all over the object. Likewise a changing magnetic field can cause an emf on a conductor and charges can migrate to one end. So those basic rules that are taught about electricity are not universal. No problem but it should be borne in mind.anorlunda said:But there is no current flow or voltage drop unless the wire is part of a closed circuit.
As some recent discussions in this forum show, that's confusing many students. You don't need necessarily a potential which would indeed restrict Ohm's law to DC situations. Ohm's Law is a transport property, i.e., it's the response of a medium to a generalized force. In this case it's the response of the conduction charges (in a usual metal conduction electrons) to an external electromagnetic field leading to the linear-response equationDale said:Also, if you have a current source then, even in a conductor you could consider the current to be creating the potential difference instead of the other way around. A conductor merely establishes a relationship between current and potential difference, it does not imply causality.
No.erocored said:As I understand potential difference is the reason of current. Does it mean that the electrostatic force creates current?
I think you are missing my main point. I guess I wasn't expressing myself clearly.vanhees71 said:As some recent discussions in this forum show, that's confusing many students.
The electrostatic force creates current in a circuit by causing the movement of charged particles, such as electrons, within the circuit. When there is a difference in electric potential between two points in the circuit, the electrostatic force will push the charged particles from the higher potential to the lower potential, creating a flow of current.
No, the electrostatic force is not the only force that creates current in a circuit. Other forces, such as magnetic forces and chemical reactions, can also contribute to the movement of charged particles and the creation of current in a circuit.
No, the electrostatic force alone cannot create current in a circuit without a power source. A power source, such as a battery or generator, is needed to create a potential difference and provide the initial push for the charged particles to move and create current.
The strength of the electrostatic force can affect the amount of current in a circuit. A stronger electrostatic force will result in a greater push on the charged particles, leading to a larger flow of current. However, other factors such as the resistance of the circuit and the number of charged particles also play a role in determining the amount of current.
Yes, the electrostatic force can create current in a circuit with non-metallic materials. Non-metallic materials, such as semiconductors, can also conduct electricity and allow for the movement of charged particles under the influence of the electrostatic force.