Magnetic field by a finite section of wire?

AI Thread Summary
The discussion centers on calculating the magnetic field at the center of a semicircular loop formed by two perpendicular wires carrying a current of 6 A. The user understands how to compute the magnetic field from the semicircle but struggles with the contribution from the two finite wires, specifically regarding the angles involved in the calculation. There is confusion about why the angles are considered to be 45 degrees instead of the expected 0 to 90 degrees, leading to incorrect results. Other participants request clarification on the shape of the setup and the reasoning behind the angle choice. The conversation highlights the need for a clearer understanding of magnetic field calculations in this specific configuration.
helpmeplz!
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hey guys i have a question. i solved the problem but i don't understand how to do it.

Two perpendicular straight wires join in the ends of a semicircular loop of radius a = 11 cm, as shown in the figure above. If the current I =6 A, what is the resultant field at the center of the circular section?

http://gauss.vaniercollege.qc.ca/webwork2/NYBramakko/Magnetic_Field/6/?effectiveUser=0954278&displayMode=images&showOldAnswers=1&user=0954278&key=bIyLRnos5NmBC26Vl4DpQdlatGJalrsW

i know how to get the magnetic field due to the semi circle, but for the two finite wires, i know from the integral we get uo I/ 4piR (sin phi1 + sinphi2). But for me when i look at each section of wire, I see the angles going from 0 to 90 degrees, so phi one is 0 degrees and phi 2 is 90 degree. Doing that gives 0. But that is obviously not right. Why do we use 45 degrees i just don't understand it? Please anyone!
 
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hi helpmeplease! :smile:

your picture is not visible (without logging in) :confused:

can you please explain the shape (particularly the 45°)? :wink:
 
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