Calculating Magnetic Field of Square Loop: Questions Answered!

AI Thread Summary
The discussion revolves around the application of the Biot-Savart law in calculating magnetic fields from current elements. A key question is whether to multiply by cos(theta) or sin(theta) when summing contributions from a system like a square loop. Participants suggest returning to the basics of the Biot-Savart law, emphasizing the importance of understanding the cross product rather than memorizing specific forms. Drawing diagrams is recommended as a helpful method to clarify the relationships involved. Ultimately, a clear understanding of the original equation is essential for accurate calculations.
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OK...
My question is, if I have so system like square loop... and all the donations be summed up by Bcos(Tetha) or sin(Tetha), am I need to multiply the cos/sin in Biot -Savart rule?
So I will get
dB=const*dx * sinTetha*cosTetha / r^2
or I just need to exchange cos with sin? (if all donations are summed up with BcosTetha)

?​

Thanks for watchers and answerers !
 
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My suggestion is its always better to go down to the basics and instead of remembering the cos(theta) form of Biot-Savart law, instead remember its CROSS PRODUCT form, that way u'd always know how to approach.
simply draw the figure check the direction and proceed, its absolutely simple if done the right way.
 
You are not answering me. If someone ask A or B, you need to say - A or B

I didn't understand - with cos or withnt?
 
Vipuldce already answered your question. I'm not going to attempt because I still do not understand your thinking here but such misunderstandings are trivial if you just go back to the original equation. The magnetic field is related to the cross product of the current element and the directional vector from your current element to the observation point.

Drawing a simple diagram and giving it some thought should clear things up for you.
 
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