Solution. We begin by writing the described force as a vector. 0.8i + 1.5j - 2k T = TAB = 2.4 0.82 + 1.52 + 22 = 0.731i + 1.371j - 1.829k kN The moment of this force about point O is Mo = roA X T = (1.6i + 2k) x (0.731i + 1.371j - 1.829k) = -2.74i + 4.39j + 2.19k kN . m Ans. This vector has a magnitude Mo = 2.742 + 4.392 + 2.192 = 5.62 kN .m Ans