Approximate inductance of a filamentary circular current loop

AI Thread Summary
The discussion focuses on calculating the inductance of a filamentary circular current loop, proposing an approximation using the magnetic field at the center of the loop. The formula derived is L = μ*Pi*radius/2, which is validated by numerical checks indicating the average magnetic field is approximately 0.93 times the center value. Participants note that traditional methods use a finite wire radius, leading to divergence when the radius approaches zero. The significance of the simple calculation is questioned, with references to auto and mutual inductance coefficients that relate magnetic flux to current. The conversation emphasizes the need for clarity on the physical implications of the simplified inductance calculation.
LydiaAC
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Hello everyone,

I want to have a simple example of an inductance calculation.

The magnetic field normal to a filamentary circular current loop is not constant over the circle but if we approximate the value as that for the center, multiply by the area of the circle and divide by the current, we get

L=mu*Pi*radius/2

I checked numerically and it seems that the average magnetic field is in fact about 0.93 of the value at the center of the circle.

However, most books go straight to calculate the inductance using a wire of finite radius and the formula diverge when this radius is zero.

I am wondering how much physical significance have the simple calculation I described above. Any help?
 
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inductance of filamentary circular loop

L = μ0*a*ln((8*a/b)-(7/4)), where a = loop radius in meters, b = wire radius in meters, μ0 = free space permeability constant = 0.4*∏μh/m.

Does this help?

Claude
 
Check the coefficient of auto inductance and mutual inductance, this coefficients give a relationship between the magnetic flux and the current source
 
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