I'm having a hard time understanding example 5.8 in Introduction to Electrodynamics by Griffiths. Why, exactly, is Ienc = KL? It makes sense intuitively, but I don't see how to get this result explicitly -- shouldn't the line integral be along the y-axis, and since [tex]\bar{K}[/tex]=K[tex]\hat{x}[/tex], shouldn't the dot product be equal to zero? If it's not along the y-axis, how is it that the integral can be from L to 0?(adsbygoogle = window.adsbygoogle || []).push({});

If anybody could explicitly do the dot product and integral that finds the enclosed current in this example (5.8 Griffiths), that would be really helpful.

Thanks for any info.

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# Griffiths Example 5.8

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