在图示平面机构中,滑块 B 可在水平滑道内运动,套管 H 可在导杆 OC 上自由滑动。已知: P = 60 kN , Q = 50 kN , OA = L 1 = 25 cm , AB = L 2 = 20 cm , b =16 cm , 不计各构件自重及各接触处摩擦。试用虚位移原理求机构在图示位置 (OC 水平 ) ,套管 H 的位 置 x 为 。
【单选题】听力原文:W: John, since you visited Tianjin last week, where do you want to go tomorrow? M: I want to visit every place here in your capital. W: Well, I'll have to make a list of the famous places for you...