【判断题】不合格数图C-CHART属于计量型管制图。( )
【简答题】【光程】用在真空中波长为 λ 的单色光,在折射率为 n 的透明介质中从 A 沿某路径传播到 B ,若 AB 两点相位差为 5 π ,则此路径 AB 的光程为波长 λ 的 _________ 倍?
【单选题】有两个同方向的简谐振动,振动方程分别为:【图片】和【图片】,它们合振动的频率和拍频分别为
【单选题】He runs fast and plays football very well. He has a good _____. [ ]
【简答题】A.He knew this beforehand. B.He judged from his common sense. C.He judged from the speeds of sound D.He judged by reading the textbook.