Luggage Railway System
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Once again, the engineers need to study the luggage transport system that was examined previously. This time, they need to understand the effects of the bending on the rail itself by determining the moments of inertia of the cross sectio with respect to an axis through the centroid of the rail.

What is known:

  • The centroid is located at x = 10.62 cm
    and y = 4.218 cm (calculated previously).
  • The dimensions of the cross section are as shown.

Centroid and Dimension Diagram

What are the moments of inertia for the entire cross section with respect to the centroidal axis?


  • Determine the moments of inertia for each individual part with respect to its centroid.
  • Use the parallel axis theorem and the method of composite parts to determine the moments of inertia for the centroidal axis of the cross section.