球形盛水容器如图所示,球体的内径d = 2 m,下半球固定,上半球用螺栓连在下半球上,试求上半球作用在螺栓上的力为（）https://image.zhihuishu.com/zhs/onlineexam/ueditor/202002/c26354d72c69451ebbc105e01cdd7cdf.png
举一反三
- 若L是上半椭圆 取顺时针方向，则 的值为( ).https://image.zhihuishu.com/zhs/onlineexam/ueditor/202002/87464b2710b74edd919a1014709f8862.png
- 半球截切后正确的水平投影是（ ）http://image.zhihuishu.com/zhs/onlineexam/ueditor/201908/2b09cedeab2a4385aa9d6bb13cd29be9.png
- 在均匀电场中，作一半径为R的半球面，使半球面的轴与场强E的方向平行，则通过这一半球面的电通量为 A: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201805/bf341a312be54f3c99c3472135e65b4d.png" /> B: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201805/75062c5d50c24d6684010689732915ac.png" /> C: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201805/47e2f56b1f234526a7582ca537740bcc.png" /> D: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201805/5284cd2d979041baaed0b04028cfb72b.png" />
- 两个半圆球形壳用螺钉相连接，球内部充满水，顶端通大气，作用在上半球壳和下半球壳上...9d8720d1abbcdd10.png
- 设A=<img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/202002/bc546fc03fdb4ba3b7e6b144b6371d7f.png" />，B=Р(Р(A)) 下列（ ）表达式不成立。 A: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/202002/6e615703da60435893f9e9a9273e12e5.png" /> B: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/202002/64c831067d054e71a6c76f43849d450d.png" /> C: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/202002/72023a5250e44c12b98923044194f13d.png" /> D: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/202002/c48e039a739c4502830eee7ae0ac1678.png" />