系统受力作用，在图示平面内处于平衡状态。则系统有_______ 个独立的平衡方程，有________个未知约束力.http://image.zhihuishu.com/zhs/onlineexam/ueditor/201901/5e97a5ca663f4dfdabae258094b04ac7.png
举一反三
- 系统受力作用，在图示平面内处于平衡状态。则系统有_______ 个独立的平衡方程，有________个未知约束力.[img=54x29]17a3da018a31cb7.png[/img]
- 系统受力[img=54x29]17d606332cbe5db.png[/img]作用，在图示平面内处于平衡状态。则系统有_______ 个独立的平衡方程，有________个未知约束力.[img=183x212]17d60633371f1e5.png[/img] A: 6；7 B: 7；3 C: 7；6 D: 6；4
- 图示曲柄连杆机构，已知曲柄OA长L，重量不计，连杆AB长2L，重P，受矩为M的力偶和水平力Ｆ的作用，在图示位置平衡。若用虚位移原理求解，则必要的虚位移之间的关系为___________，力F的大小为_____________________。<img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201901/be06434307bd424abfc4ebfe02661f7a.png" /> A: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201901/b8e7b964d1c84aeca7b22ddef4de87a2.png" />;<img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201901/a584946cde17410c945d6611ff2113b5.png" /> B: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201901/1aaef24e28ee477ab25dae0a400bf23f.png" />;<img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201901/f3b395453e1d48bdadff2e37dfbbb626.png" /> C: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201901/be37912822f0451bb15639b7fa0589f1.png" />;<img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201901/6d1112b5c1b4446b93578138388ed79f.png" /> D: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201901/89b7bcef6b51410cb624a654747d56ee.png" />;<img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201901/0e2b78f437914a1eb8327d13185eaedf.png" />
- What are the comedies of Shakespeare? A: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201901/1882addb95d34f3e877db8ec62e82507.png"/> B: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201901/4e230d2e03cc46c2b717155e90fdd081.png"/> C: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201901/7f4368645eff4e4b9ec89b237843dabd.png"/> D: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201901/5ccbfc9718084d318abfbbe254ae048b.png"/>
- Which one is Homer’s epic? A: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201901/60a09e42c1cb4c988adcf2fa43a2170c.png"> B: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201901/148a547a82cd4f5482de272b09415b7f.png"> C: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201901/bc77b52b6ae747fda43ef56a09994b9f.png"> D: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201901/9a18e23e6d9a453ea18eaabd88d99376.png">