Engineering Board Exam Reviewer · Applications: Centroid, Work, and Moment of Inertia · easy

A 4-m rod has linear density (x)=3x kg/m, where x is measured from the left end. Find its moment of inertia about the left end, in kg·m2.

  1. 128
  2. 384
  3. 96
  4. 192

Answer

D. 192

Solution

I= 04x2(3x),dx=3x4/4 |04=192 kg·m2.

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