determine the weight of the crate knowing that the tension in cable AB is 3kN
确定机箱（或装货箱）的重量,从而了解到在缆索AB上的张力为3kN（千牛顿）
vector mechanics for engineers statics and dynamics 8th edition
《工程师静力学和动力学用矢量力学》
说明：cable翻缆索比较确切,绳索是rope
vector mechanics翻成矢量力学比较好
statics和dynamics分别是静力学和动
力学