Is the Curl of Induced E Field Always Zero?

AI Thread Summary
The curl of the electric field (E-field) is zero only in electrostatics, indicating a conservative force. In dynamic situations, such as when there are changes in magnetic flux, the curl of the E-field is related to the negative rate of change of the magnetic field, making it non-conservative. This results in a circular induced electric field, which contradicts the conservative nature of electrostatic fields. The path integral around a closed loop in this dynamic case is equal to the electromotive force (EMF) driving the current. Therefore, the claim about zero curl applies strictly to static electric fields.
Sturk200
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I have a problem. So the curl of the E field is supposed to be zero always, which tells us that it is a conservative force (path independence and scalar potential and so on). But what about the fact that the induced electric field consequent upon changes in magnetic flux is circular? Doesn't this mean that if we sustained such a field we would have a non-conservative electric field?

Is this a problem, or is it just that the claim about electric fields having zero curl has application only to electrostatics?
 
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Sturk200 said:
I have a problem. So the curl of the E field is supposed to be zero always, which tells us that it is a conservative force (path independence and scalar potential and so on). But what about the fact that the induced electric field consequent upon changes in magnetic flux is circular? Doesn't this mean that if we sustained such a field we would have a non-conservative electric field?

Is this a problem, or is it just that the claim about electric fields having zero curl has application only to electrostatics?

The curl of the E-field is zero only if the E-field is time independent, i.e. electrostatics. In the dynamic case, the curl of the E-field is the negative rate of change of the B-field, which is not zero in general. This makes the dynamic E-field non-conservative, with the path integral around a closed loop equal to the EMF in the circuit which drives the current.
 
Sturk200 said:
the curl of the E field is supposed to be zero always
No, ##\nabla \times E=-\partial B/\partial t##
 
Last edited:
DaleSpam said:
No, ##\nabla \times E=\partial B/\partial t##
Don't forget the negative sign.
 
MarcusAgrippa said:
Don't forget the negative sign.
Oops, fixed it.
 
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