，瞬时速率为
，某一段时间内的平均速度为
，平均速率为
，它们之间的关系必定有（ ）A:
B:
C:
D:
举一反三
- 拉普拉斯（Laplace）方程的表达式为（ ）。 A: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201812/26731bcad75f41389448b29292940653.jpg" /> B: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201812/40e7e55a72ee44f59b45d20c84ebe3a6.jpg" /> C: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201812/c65a79ea4d754174b99f34020d6e1735.jpg" /> D: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201812/139e8d3dc37941549e7b6b1731243172.jpg" />
- 平面一维稳定渗流的压力分布公式为（ ）。 A: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201812/d08348f3b84f442d87994311dc13686b.jpg" /> B: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201812/2df214c86c5e4103897ba81ce2c6cd98.jpg" /> C: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201812/cc98e4a778cc463c965ac8115e028f86.jpg" /> D: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201812/bc82177c19d44acfa1b365c3d66ed0a4.jpg" />
- 图示单元体应力状态，沿x方向的线应变εx可表示为（ ）。 <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201812/9fdd7efe625f4047bb61ef38f5aea871.png" /> A: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201812/5da2d36f7ef84cbc8396b1e27b775bf4.png" /> B: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201812/164a3d85fdb6462696d83d62b92b2435.png" /> C: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201812/9e37e58e1c12442e8e018c0af637dfdf.png" /> D: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201812/41fd81417e5f47bea1db35fed7c2c44e.png" />
- 下列四种产品中，（）属于主体附加。 A: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201812/7de8bb1790ee4eccbc8fe23d663cb293.JPG" /> B: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201812/9f76d9ce04cb4729b4739bdd64d5917b.JPG" /> C: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201812/b4d8b1ab0b9c4f5e8d165f7afd487e00.JPG" /> D: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201812/4862f4e33e114c63bcfa3ebf5c112cba.JPG" />
- 下列四种产品中，（）属于同类组合。 A: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201812/ee5cc627e4a243ea8fc5025d6736de65.JPG" /> B: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201812/95326815255349e7bb11324655294818.JPG" /> C: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201812/07ebf5a3e62b47d2be75f2574f2bee3e.JPG" /> D: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201812/a46447046f5340d8977c1ffed9a70772.JPG" />
内容
- 0
下列四种产品中，（）属于重组组合。 A: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201812/dd09946bf045417895c8f6ff58a1204f.JPG" /> B: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201812/471a61333c8540d7a058dc69c952e11a.JPG" /> C: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201812/feef7f0c86bf46b09e4376f35f6f8bd9.JPG" /> D: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201812/808892c484f74ea18b075dcf9bb17d08.JPG" />
- 1
平面径向活塞式水驱油过程中，纯水区的流量为（ ）。 A: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201812/f8a3355fd37b400b86f9d4e17130c493.png"/> B: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201812/9b416b4e31514c9e9e086fdf179744b1.png"/> C: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201812/08dec96d094b4f039fd625b22fcc376f.png"/> D: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201812/eedcbf5542044303a218a2df52da0771.png"/>
- 2
下列积分中能用牛顿-莱布尼兹公式的是（ ）。 A: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201812/379f5cddb00442c9b40088a96c1ffa37.png" /> B: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201812/5ba6eb575adc4b6e843f8da192b341eb.png" /> C: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201812/58ec1ed0be3f4cdead7cf900d12681fe.png" /> D: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201812/a4eab4fe9e9c4fe0b56a15f4678d5e06.png" />
- 3
质点作半径为R的变速圆周运动时的加速度大小为（v表示任一时刻质点的速率）( ) A: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201812/566625ddf2c44d81babb2fdd6c1215b2.png" /> B: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201812/bceb93f381844a3988a0291fea01e102.png" /> C: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201812/e43ab8d2b7b4422a9088f99e594718cb.png" /> D: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201812/b1a89995aed242d9b12b93495a7ebdae.png" />
- 4
在绘制程序流程图时，表示“条件判断”的符号是【 】 A: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201812/999737d003564abda13a025e003fda97.png" /> B: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201812/e471e08876184d45939dd8639058a382.png" /> C: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201812/9a703316d25940e4b089eb336deaa0da.png" /> D: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201812/202e22615902455e95ca7025184f1c62.png" />