Polar Moment of Inertia

I_{p} = {\sum x_{i}^{2}}_{i = 1}^{n} + {\sum y_{i}^{2}}_{i = 1}^{n}

I_p	Polar moment of inertia without component of fastener surfaces
x_i	Distance from the centroid of the fastener group to the fastener in the x-direction
y_i	Distance from the centroid of the fastener group to the fastener in the y-direction

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