图示两端铰支压杆的截面为矩形，当其失稳时，（ ）
A: C
B: A
C: B
D: D
A: C
B: A
C: B
D: D
举一反三
- 如图所示电路的逻辑表达式F=（ ）。<img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201909/8655693a417e4e43a32e0732ed533c96.png" /> A: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201909/beda73211aea49f082d9137fd4eb0526.png" /> B: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201909/7388c99ee0824f20bcf85893934a2f6a.png" /> C: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201909/9a5c81e78b344c79a9389e932a7f55ce.png" /> D: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201909/82193a9a030243728012b02e15718987.png" />
- 外径为D、内径为d的空心圆轴，其扭转截面系数为（ ）。 A: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201909/af42d1bd70034c0d85f2f419a2839f22.png" /> B: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201909/2e74a84c10d14288a269b7b8def735f1.png" /> C: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201909/55aca62def3e4c9485e9b0894a63a342.png" /> D: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201909/6ed4e2143b6a4c82ad03319473bb6a3a.png" />
- 单筋矩形截面受弯构件正截面承载力计算的基本公式适用条件不包括 A: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201909/5b801d200a534980a307a3cb99810fba.png" /> B: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201909/ec299665c7d544b9b5d3b03075a613cb.png" /> C: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201909/a5961b74c3c3423fa3ba1aaa49e779e1.png" /> D: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201909/b119dbfce14a487ea5e13e6625026f25.png" />
- 线性谐振子的第一激发态的波函数为<img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201909/aab7a58985f443ed91a9f4036d4b56dd.png" />,其位置几率分布最大处为 A: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201909/44c963c6379540a099bfd79da6501b42.png" /> B: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201909/dff9139c15174797b8b68ef230d1ee90.png" /> C: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201909/ad088197932f430db9416ebf9d5b47fa.png" /> D: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201909/17949074010c4d44ad48b416055aaa86.png" />
- 如图示并联管路，已知各支路的沿程阻力系数之比为<img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201909/6e209020d20f4543823ce6516ae8ca06.png" />，管长之比为<img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201909/50814fe028094040bc955d8e1542b6d2.png" />，且<img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201909/40b4c6a9565b483590c5c7d607e7ed66.png" />，则两支管的流量之比<img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201909/1055534bfce6426a94682ba086a5b17e.png" />=（）。<img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201909/77815369f5cd41f3a2e68b9524b454c5.png" /> A: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201909/0cd231eebe45465f941a0f614743e6d2.png" /> B: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201909/7555afa5223e40bf89ca575cf7b52754.png" /> C: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201909/1b06cd474b844644a6d97ad87d208e94.png" /> D: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201909/d0b2bca045414236a7d1c9925a9264f2.png" />