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<h2 class="hd hd-2 unit-title">An Introduction to Magnetic Data Storage</h2>
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<h3 class="hd hd-2">An Introduction to Magnetic Data Storage</h3>
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<h2 class="hd hd-2 unit-title">Longitudinal Magnetic Recording</h2>
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<h3 class="hd hd-2">Longitudinal Magnetic Recording</h3>
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<h2 class="hd hd-2 unit-title">Perpendicular Magnetic Recording</h2>
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<h2 class="hd hd-2 unit-title">Magnetic Recording Media</h2>
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<h2 class="hd hd-2 unit-title">In-Lecture Question 9.3</h2>
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<p>Several types of magnetic devices, including transformers, electromagnets, and hard disk write heads, consist of a current-carrying coil wrapped around a magnetic core (or pole piece). </p>
<p>What is the purpose of the magnetic core? </p>
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