The rotational inertia of a solid uniform sphere about a diameter is (2/5)MR², where M is its mass and R is its radius.If the sphere is pivoted about an axis that is tangent to its surface, its rotational inertia is: A)MR² B)(2/5)MR² C)(3/5)MR² D)(5/2)MR² E)(7/5)MR²

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Quizplus · Accepted Answer

The parallel axis theorem states that I = I_cm + Md^2, where I_cm is the rotational inertia about the center of mass, M is the mass, and d is the distance from the center of mass to the new axis. For a sphere, I_cm = (2/5)MR^2 and d = R, so I = (2/5)MR^2 + MR^2 = (7/5)MR^2.

The Rotational Inertia of a Solid Uniform Sphere About a Diameter