Finding ∫B·dl for a loop not enclosing a current

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TSny said:
Yes, everything looks good. I was misinterpreting how you were using the word "equivalent". I thought you were implying that the semicircle current (alone) and the D loop produce the same result for the integral of Bnet around the circular path.

What if you replaced the semicircular current from A to B with a current of a different shape, such as shown in the attachment?

Are the points A and B along the axis of the integration circle?
 
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If A and B are along the axis I would say the OP's a is correct but not b or c.

(I might as well benefit from this too!) :biggrin:
 
rude man said:
If A and B are along the axis I would say the OP's a is correct but not b or c.

I wish TSny is a bit lenient in his marking :wink:. I somehow have the feeling that getting one answer correct should be enough to pass the test :-p.
 
rude man said:
Are the points A and B along the axis of the integration circle?

Yes, I should have made that clear. A and B are still in the same location relative to the path of integration.
 
Tanya Sharma said:
I wish TSny is a bit lenient in his marking :wink:. I somehow have the feeling that getting one answer correct should be enough to pass the test :-p.

Well, I'm retired. So, I refuse to do any more grading! :-p
But, if you were to use Tanya's suggested grading scheme, then you both passed. Tanya gets A+ on this one. (That is, her answers agree with mine, anyway.)
 
Wow ! I can't believe I topped the class :-p

Have to say the Prof. is really cool :biggrin:.
 
TSny said:
Well, I'm retired. So, I refuse to do any more grading! :-p
But, if you were to use Tanya's suggested grading scheme, then you both passed. Tanya gets A+ on this one. (That is, her answers agree with mine, anyway.)

Tanya's answers for b and c seem to have the wrong sign, otherwise I agree.

A downward current gives a positive B circulation as I understand it.
 
Tanya Sharma said:
Wow ! I can't believe I topped the class :-p

Have to say the Prof. is really cool :biggrin:.

Congrats! And yes, we owe Dr. T. one - or actually several by now!
 

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