Solving Biot-Savarts Law for Finite Thickness Current Loops

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The discussion centers on the application of Biot-Savart's law to a current loop with finite thickness, specifically questioning how to accurately account for this thickness in the magnetic field calculation. The standard formula for the magnetic field on the axis of a loop assumes infinitesimal thickness, which raises concerns about its accuracy for real-world applications. One suggested approach is to model the thick coil as multiple narrow coils connected in parallel, allowing for a more precise integration. Additionally, there is a query regarding a potential missing factor of 2π in the equation provided. The conversation highlights a gap in standard electrodynamics resources, such as Griffiths' textbook, regarding this topic.
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Hi

When solving Biot-Savarts law for a current loop of radius R, the magnetic field on the axis of the loop is given by (in Tesla)
<br /> B(z) = \mu_0I\frac{R^2}{(R^2+z^2)^{\frac{3}{2}}}<br />
where I is the current through the loop. However, this derivation assumes that the loop has an infinitesimal thickness. But how is the "proper" way to take into account the fact that a current loops has a finite thickness?

My book on Electrodynamics (Griffiths) does not address this issue, and it is something I have thought about for some time.Niles.
 
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Niles said:
Hi

When solving Biot-Savarts law for a current loop of radius R, the magnetic field on the axis of the loop is given by (in Tesla)
<br /> B(z) = \mu_0I\frac{R^2}{(R^2+z^2)^{\frac{3}{2}}}<br />
where I is the current through the loop. However, this derivation assumes that the loop has an infinitesimal thickness. But how is the "proper" way to take into account the fact that a current loops has a finite thickness?

My book on Electrodynamics (Griffiths) does not address this issue, and it is something I have thought about for some time.


Niles.

I suppose by carrying out a more sophisticated integration where,perhaps,the thick coil can be considered as a number of narrow coils connected side by side and making good electrical contact with each other.

(Is your equation missing a 2pi?)
 
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