Solved: A cylinder of iron is placed so that it is free to
Chapter 28, Problem Q28.20(choose chapter or problem)
A cylinder of iron is placed so that it is free to rotate around its axis. Initially the cylinder is at rest, and a magnetic field is applied to the cylinder so that it is magnetized in a direction parallel to its axis. If the direction of the external field is suddenly reversed, the direction of magnetization will also reverse and the cylinder will begin rotating around its axis. (This is called the Einsteinde Haas effect.) Explain why the cylinder begins to rotate.
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