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Question 6.9: A short circular cylinder of radius a and length L carries a...

A short circular cylinder of radius a and length L carries a “frozen-in” uniform magnetization M parallel to its axis. Find the bound current, and sketch the magnetic field of the cylinder. (Make three sketches: one for L≫a, one for L≪a, and one for L ≈ a.) Compare this bar magnet with the bar electret of Prob. 4.11.

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K _{b}= M \times \hat{ n }=M \hat{\phi}

[The external fields are the same as in the electrical case; the internal fields (inside the bar) are completely different—in fact, opposite in direction.]

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