created at May 1, 2021

Circle

Area:

A=πd24A=\frac{\pi \cdot d^{2}}{4}

Perimeter:

L=πdL=\pi \cdot d

Moments of inertia:

Ix=Iy=πd464;Iρ=πd432;I_{x}=I_{y}=\frac{\pi \cdot d^{4}}{64};\quad I_{\rho}=\frac{\pi \cdot d^{4}}{32};

Moments of resistance:

Wx=Wy=πd332;Wρ=πd316;W_{x}=W_{y}=\frac{\pi \cdot d^{3}}{32};\quad W_{\rho}=\frac{\pi \cdot d^{3}}{16};

Radius of inertia:

ix=iy=d4i_{x} = i_{y} = \frac{d}{4}