问题
应用设计题
如图所示,当人曲臂将重物端起时,人的前臂可以看作一个杠杆,请在示意图上画出F1和F2的力臂.
答案
如图所示
题目分析:支点到力的作用线的距离叫做该力的力臂。过支点O分别作力F1、F2作用线的垂线段L1、L2就是F1、F2的力臂。如图所示。
如图所示,当人曲臂将重物端起时,人的前臂可以看作一个杠杆,请在示意图上画出F1和F2的力臂.
如图所示
题目分析:支点到力的作用线的距离叫做该力的力臂。过支点O分别作力F1、F2作用线的垂线段L1、L2就是F1、F2的力臂。如图所示。
完形填空。 I am fine here 1 China. I 2 classes with Chinese 3 . Now I have 4 Chinese friends. They teach me Chinese and I teach 5 English . I can 6 a little Chinese now. In the afternoon, we sing and 7 games. My school is 8 very big, but 9 is very nice, It is 10 a river. Sometimes we go to swim in the river. We go to school five days every week. On Sunday I go shopping with my Chinese friends. I have a good time here. Don't worry about me, mother. | ||||
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