Polar Moment of Inertia of a Trapezoid

Polar Moment of Inertia of a Trapezoid formulas
\( J_{z} \;=\; I_x + I_y \) \( J_{z1} \;=\; I_{x1} + I_{y1} \)
Symbol	English	Metric
\( J \) = torsional constant	\( in^4 \)	\( mm^4 \)
\( I \) = moment of inertia	\(lbm \;/\; ft^2-sec\)	\(kg \;/\; m^2\)