两构件组成一般情况的高副即非纯滚动高副时，其瞬心就在高副接触点处。
查看答案
在机构运动分析图解法中，影像原理不仅适用于已知同一构件上二点速度或加速度求第三点的速度和加速度，也适用于不同一构件上二点速度或加速度求第三点的速度和加速度。
A. 对
B. 错
Mini-DialoguesWhere does this conversation most probably take place?[音频]
At a marine exhibition.
B. On a fishing boat.
C. At a restaurant.
D. In a fish shop.
Mini-DialoguesWhat do we learn from this conversation?[音频]
A. The man went to Australia during Christmas.
B. The man visited Australia during the summer vacation.
C. The man didn't have a good time because nobody was home.
D. The man remained home while his parents went to see his uncle.
Mini-DialoguesWhat was Shelley going to do?[音频]
Attend a party at a classmates's home
B. Do homework with her classmate.
C. Attend an evening class.
Dine out with her classmate.
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