एक वृत्त के चतुर्थांश (quadrant circle) के केंद्रक (centroid) की इसकी सीधी सीमावर्ती त्रिज्याओं से दूरी क्या होगी, (जहाँ 'r' वृत्त की त्रिज्या है)?

According to the perpendicular axis theorem, the moment of inertia of a plane area about an axis normal to the x-y plane passing through the origin is given by:

The expression for the moment of inertia of a rectangular section of width 'b' and depth 'd' about an axis passing through its base is: