<Dl> <Dd> T max = τ max J z r (\ displaystyle T_ (\ max) = (\ frac (\ tau _ (\ max) J_ (z)) (r))) </Dd> </Dl> <Dd> T max = τ max J z r (\ displaystyle T_ (\ max) = (\ frac (\ tau _ (\ max) J_ (z)) (r))) </Dd> <P> After substitution of the polar moment of inertia the following expression is obtained: </P> <Dl> <Dd> r = 2 T max π τ max 3 (\ displaystyle r = (\ sqrt ((3)) (\ frac (2T_ (\ max)) (\ pi \ tau _ (\ max))))) </Dd> </Dl>

Polar second moment of area vs second moment of area