A non-uniform rod of length L and mass M is pivoted about one end.The moment of inertia of this rod about its pivoted end is 1ML²/4.Attached to the rod is a mass 3M at its midpoint and at the end opposite the pivot is another mass 2M.What is the moment of inertia of this configuration about the pivot? A)3ML² B)2ML² C)4ML² D)5ML² E)None of the above answers is correct.

Question

Quizplus · Accepted Answer

The moment of inertia of the rod is given as (1/4)ML². The mass 3M at the midpoint contributes (3M)(L/2)² = (3/4)ML². The mass 2M at the end contributes (2M)(L)² = 2ML². Adding these gives (1/4)ML² + (3/4)ML² + 2ML² = 3ML².

A Non-Uniform Rod of Length L and Mass M Is