Magnetic field, current with arced path

AI Thread Summary
The discussion focuses on calculating the magnetic field due to a current with an arced path using the Biot-Savart law. The user derives the magnetic field expression and simplifies the integral, ultimately arriving at a value of 2.618x10^-7 T. They express confidence in their calculations but seek confirmation of their logic and the direction of the magnetic field. The user acknowledges a potential alternative approach to the integral but notes that it yields the same result. The main concern remains ensuring the accuracy of both the magnitude and direction of the magnetic field.
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Homework Statement


attachment.php?attachmentid=63204&d=1382399172.png

Homework Equations


The Attempt at a Solution


B=\frac{\mu_{0}I}{4\pi}\int \frac{dl\times \hat{r}}{r^{2}}=\frac{\mu_{0}I}{4\pi r^{2}}\int dl\times \hat{r}
So I think since when you cross dl with r, you end up with just dl.
\frac{\mu_{0} I}{4\pi r^{2}}\int dl
l=rθ so dl=rdθ, substituting:
\frac{\mu_{0} I}{4\pi r^{2}}\int rd\theta=\frac{\mu_{0} I}{4\pi r}\int d\theta=\frac{\mu_{0} I}{4\pi r}\theta
Plugging in values I end up with: 2.618x10-7 T

Just need someone to look over work/logic, I think it's correct.
 

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Just realized I could of just done the integral at ∫dl and plugged in rθ after, but whatever. Same result.
 
Magnitude is correct.

Direction?
 
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