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

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SUMMARY

The discussion focuses on deriving the magnetic field for a current loop, specifically addressing the angles involved in the calculations. The formula discussed is ##\frac {ds * r} {r^2}##, which simplifies to ##ds \sin \theta##. The confusion arises from the distinction between the azimuthal angle (##\phi##) related to the current loop and the angle (##\theta##) that describes the orientation of the magnetic field element ##d\vec B##. Clarification is sought on these angles and their relevance in the derivation process.

PREREQUISITES
  • Understanding of magnetic fields generated by current-carrying conductors
  • Familiarity with vector calculus, particularly in three-dimensional space
  • Knowledge of trigonometric functions, specifically sine and angles in context
  • Basic principles of electromagnetism, including Biot-Savart Law
NEXT STEPS
  • Study the Biot-Savart Law for calculating magnetic fields from current distributions
  • Learn about the geometry of circular current loops and their magnetic field characteristics
  • Explore vector calculus applications in electromagnetism, focusing on angle calculations
  • Investigate the relationship between azimuthal and axial angles in magnetic field derivations
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Physics students, electrical engineers, and anyone interested in understanding the derivation of magnetic fields from current loops and the associated geometric considerations.

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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