How are the angles involved in deriving magnetic fields for a current loop?

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The discussion focuses on deriving the magnetic field for a current loop, specifically addressing the confusion around the angles involved in the calculations. The formula presented includes the term ##ds \sin \theta##, which raises questions about the correct interpretation of the angle θ. Participants clarify that there are two angles to consider: the azimuthal angle for the current loop element and the angle between the magnetic field element and the axis. The conversation emphasizes the need for precise definitions of these angles to avoid ambiguity in derivations. Understanding these angles is crucial for accurately calculating the magnetic field at a point along the axis of the loop.
jisbon
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Homework Statement
Derive magnetic field at a point p away generated by current carrying loop and line.
Relevant Equations
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So I have managed to derive the magnetic field of a current carrying wire, however, I seem to have some enquiries on deriving the one for the loop. In the formula where ##\frac {ds * r} {r^2}##, I know that it will become ##ds sin \theta.## However compared to the theta in the wire, the theta that most derivations (I was searching for solutions) seems to be the angle at the point instead of the angle from the loop. Anyone can shine a light on this? Thanks
 
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Bit hard to decipher your question without a drawing. Can I assume you are looking at the field in a point on axis ?
jisbon said:
most derivations
Utterly vague. Mention one or two explicitly.

Oh, and: ##\ dssin\theta\ ## looks ugly; at least use \sin : ##ds\sin\theta##
 
If you are considering the magnetic field due to a circular current loop at some point ##z## on the axis of the loop, there are two angles involved, one is the azimuthal angle (normally labeled ##\phi##) that locates element ##d\vec s## on the current loop and the second angle (normally labeled ##\theta##) is the angle between the field element ##d\vec B## and either the ##z##-axis or one of the horizontal axes (see image below). Are these the angles you mean respectively by "theta in the wire" and "the angle at the point"?

Loop.png
 
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