Question

Locate the centroid of the I-section shown in Fig. 

Answer 1

Selecting the coordinate system as shown in Fig. due to symmetry centroid must lie on y axis, 

i.e., \(\bar x\) = 0 

Now, the composite section may be split into three rectangles 

A₁ = 100 × 20 = 2000 mm² 

Centroid of A₁ from the origin is:

Thus, the centroid is on the symmetric axis at a distance 59.71 mm from the bottom as shown in Fig.