Questions
Question 1
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A body has \(I_{\mathrm{cm}}=0.20\,\mathrm{kg\,m^2}\), mass \(3.0\,\mathrm{kg}\), and axis offset \(d=0.40\,\mathrm{m}\). Find \(I\).
Question 2
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A uniform rod has \(M=2.0\,\mathrm{kg}\) and \(L=1.2\,\mathrm{m}\). Using \(I_{\mathrm{end}}=\frac{1}{3}ML^2\), find its moment of inertia about one end.
Question 3
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In the added term \(Md^2\), what happens to the added moment of inertia if \(d\) doubles?
Question 4
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A solid disk has \(M=5.0\,\mathrm{kg}\), \(R=0.20\,\mathrm{m}\), and \(I_{\mathrm{cm}}=\frac{1}{2}MR^2\). Find \(I\) about a parallel axis \(0.10\,\mathrm{m}\) from the center.
Question 5
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A uniform rod has \(M=3.0\,\mathrm{kg}\) and \(L=2.0\,\mathrm{m}\). Find \(I\) about an axis parallel to its center axis but \(0.50\,\mathrm{m}\) from the center.
Question 6
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An object's moment of inertia about a shifted axis is \(2.0\,\mathrm{kg\,m^2}\). If \(M=4.0\,\mathrm{kg}\) and \(d=0.50\,\mathrm{m}\), find \(I_{\mathrm{cm}}\).
Question 7
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A measured shifted-axis moment of inertia is smaller than \(Md^2\). Explain why that cannot be consistent with the parallel-axis theorem for a real object.
Question 8
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A uniform rod of mass \(2.0\,\mathrm{kg}\) and length \(1.0\,\mathrm{m}\) has a \(0.50\,\mathrm{kg}\) point mass attached at one end. Find \(I\) about an axis through the rod center and perpendicular to the rod.
Question 9
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Two identical disks of mass \(m\) and radius \(R\) are fixed at the ends of a massless bar of length \(L\). The rotation axis passes through the bar midpoint and is parallel to each disk's symmetry axis. Derive \(I_{\mathrm{tot}}\), stating the modeling assumptions.
Question 10
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Two point masses \(m_1\) and \(m_2\) lie on a line at \(x=0\) and \(x=L\). For a rotation axis perpendicular to the line at position \(x\), derive the value of \(x\) that minimizes \(I\), and find the minimum \(I\).