Mechanical Engineering - Engineering Mechanics - Discussion

Nice ans, Thanks for explaining.

A1 = 100*50 = 5000 a2= 50*100 = 5000.

Flange horizontal section will be A1 and Y1 ,Y1 = (100+50/2) = 100+25 = 125.
web vertical section will be A2 Y2 , Y2= 100/2 = 50.
Cg = (a1*yi + a2*y2)/(a1+a2).
= {(5000*125) + (5000*50)}/(5000+5000),
= 5000(125+50)/ 5000 (1+1),
= 125+50/2,
= 87.5.

Horizontal section (flange) = length, 100mm, height 50mm.

Same applies to its vertical section Because the total height of both horizontal and vertical section is 150mm.

Therefore, Horizontal section (A1) = Area, 100 x 50 = 5000mm2, Centroid to bottom = 125mm (i.e.half of 50mm + 100mm),

Vertical section (A2), Area = 100 x 50=5000mm2, centroid to bottom = 50mm (i.e half of 100mm).

Centre of gravity, y = (5000 x 125) + (5000 x 50), i.e. sum of areas x centroid, divided by (5000+5000, i.e.sum of areas), ans = 87.5mm.

a1 = 100*50 = 5000; a2 = 50*100 =5000;

y1 = 50; y2=125;

cg = (a1*y1+a2*y2)/(a1+a2).

150 = 87.5.