【简答题】完形填空. Mr. Clarke works in a middle school. He likes reading and often __1__ some books from the library. He keeps __ 2 __ to the radio every morning and reading __ 3 __ after supper. So he knows much...
【单选题】As soon as Jennifer asked his name and address the man rang off.
【多选题】下列那种情况学生不能获得毕业论文答辩的资格( )。
【单选题】推拿手法的分类,除了以施力方向,动作形态,应用对象等分类,h还以什么分类?
【判断题】Public distance ranges from direct physical contact to a distance of about 45 centimeters.
【单选题】如图所示,定滑轮的两边用绳索悬挂物块A和物块B,已知物块A的重力GA=2000N,物块B的重力GB=3000N,不计绳索、滑轮的质量及各接触的摩擦,则物块A的加速度为( )。
【简答题】Translate the following paragraphs into Chinese. No one can think of Citroën car without thinking of its founder, an outstanding engineer Andre Citroën . He started a “V gear works” in 1912 and produc...
【单选题】如图所示,表面光滑的固定斜面顶端安装一个定滑轮,小物块 A 、 B 用轻绳连接并跨过定滑轮(不计滑轮的质量和一切摩擦).初始时刻,用手按住物块 B 使 A 、 B 处于静止状态.松手后 A 下落、 B 沿斜面上滑.则从松手到物块 A 着地前的瞬间
A.
由于绳子的拉力做功,所以以 A , B 为系统机械能不守恒
B.
轻绳对物块 B 做的功等于物块 B 的机械能增加量
C.
物块 A 的重力势能的减少量等于物块 A 和 B 的动能增加量
D.
物块 A 的机械能与物块 B 的重力势能之和是增加的