Does a wire loops' magnetic field affect it's current?

In summary, when current is run through a circular wire, it generates a magnetic field which can affect the current in the wire. This creates a self-induced emf, known as a 'back emf', which opposes the current flow. Eventually, this effect decreases and the current reaches a steady value determined by the wire's resistance. Inductors with more turns and an iron core have higher inductance and take longer for the current to settle, while smaller loops have a quicker settling time.
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Addez123
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When you run current through a circle formed wire it generates a magnetic field. Will this field affect the current in the wire that generates it?

I mean if it does wouldn't the calculations for the created magnetic field be rather circular?
The magnetic field depends on the current which in turn depends on magnetic field which depends on current and so on..
 
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Whilst the current is actually changing, there is a self induced emf in the circle. (read about Self Inductance) This is referred to as a 'back emf' because it acts against the current flow. (Lenz's Law) This effect decreases to zero eventually and the current reaches a steady value which is governed only by the DC resistance of the wire. An Inductor with very many turns of wire and an iron core will have such a high inductance that the current may take several seconds to establish itself. A small loop of wire may take only a few ns to settle down.
Edit: PS Welcome - I only just noticed that you're new here.
 
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Related to Does a wire loops' magnetic field affect it's current?

1. How does a wire loop's magnetic field affect its current?

The magnetic field of a wire loop can affect its current by inducing an electromotive force (EMF) in the wire. This EMF can cause a current to flow in the wire, known as an induced current. The strength of the magnetic field and the rate of change of the field can determine the magnitude of the induced current.

2. What is the relationship between a wire loop's magnetic field and its current?

The relationship between a wire loop's magnetic field and its current is described by Faraday's law of induction. This law states that a changing magnetic field will induce an EMF in a conductor, which in turn will cause a current to flow.

3. Can a wire loop's magnetic field affect its own current?

Yes, a wire loop's magnetic field can affect its own current through self-induction. This occurs when a changing magnetic field in the wire loop induces an EMF in the same wire loop, causing a current to flow. This can create a feedback loop, where the induced current creates a magnetic field that further changes the original magnetic field, resulting in a continuously changing current.

4. How does the direction of a wire loop's magnetic field affect its current?

The direction of a wire loop's magnetic field can affect its current by determining the direction of the induced current. The induced current will always flow in a direction that opposes the change in the magnetic field, as described by Lenz's law. This means that the direction of the induced current will depend on the direction of the changing magnetic field.

5. Can the current in a wire loop affect its own magnetic field?

Yes, the current in a wire loop can affect its own magnetic field through the right-hand rule. When a current flows through a wire, it creates a magnetic field around the wire in a circular pattern. The direction of this magnetic field can be determined using the right-hand rule, where the thumb points in the direction of the current and the curled fingers indicate the direction of the magnetic field.

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