Anemodia

Lab · Engineering Mechanics

Mass Properties Lab

Build a composite planar section, then read its geometry and its mass properties side by side. For uniform density the centroid and centre of mass coincide; with non-uniform density they generally differ.

Section

+x+yAC
1 solid component and 0 cutouts; geometric centroid at (0.000, 0.000) m.
  • Solid component — filled outline
  • Cutout — dashed outline, negative area
  • · component centroid
  • C — geometric centroid
  • G — centre of mass
  • Dashed through C — centroidal x̄ / ȳ axes
  • 1 / 2 — principal axes through C
  • a — custom axis through A, long-dashed

Geometric centroid C

(0, 0) m

Area-weighted; independent of density.

Centre of mass G

Not defined

Define mass or density for every component.

Components

  • Shape
    PositionMaterial & mass
    Material
    Mass model

    Rectangle · solid · no mass defined

1 of 16 components.

Diagnostics

Components combine algebraically: overlapping solids are counted twice and a cutout is not checked for containment. Model each region once.

What this Lab models

A composite planar section built from rectangles, circles, semicircles and triangles (with cutouts), analyzed for its geometric centroid and second moments of area and, separately, for its mass properties when a mass or density is defined for every component.

Focused calculators