Hello. This is a great set of lectures. I have a question about the example 11.5 (and 11.6). Why can we do the calculations only for the upper and lower parts of single crossection? The wire is wrapped around the center, so the current is flowing in more points than just 2 mentioned. The lengh of the wire (in 11.5) is 2*pi*a*d. Shouldn't that be taken into account?
Great video and great course overall, just one question at the last Example 11.6 : why is the circumference d chosen instead of 2*pi*a ? Looking forward for your answer, thank you.
Shili, Glad you liked the video. It would be just as correct to use 2*pi*a as to use d for the circumference. They are interchangeable. Here, I used d because it is helpful to see the similarity with the previous example. Thanks! Doug Tougaw
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Hello. This is a great set of lectures.
I have a question about the example 11.5 (and 11.6). Why can we do the calculations only for the upper and lower parts of single crossection? The wire is wrapped around the center, so the current is flowing in more points than just 2 mentioned. The lengh of the wire (in 11.5) is 2*pi*a*d. Shouldn't that be taken into account?
Great video and great course overall, just one question at the last Example 11.6 : why is the circumference d chosen instead of 2*pi*a ?
Looking forward for your answer, thank you.
Shili,
Glad you liked the video. It would be just as correct to use 2*pi*a as to use d for the circumference. They are interchangeable. Here, I used d because it is helpful to see the similarity with the previous example.
Thanks!
Doug Tougaw
i love your course. Eq 11.4 should it not be a negative before the second term?