http://image.zhihuishu.com/zhs/onlineexam/ueditor/201801/532cfa196ddd479aaaa30c9c02c23e57.png

http://image.zhihuishu.com/zhs/onlineexam/ueditor/201801/cc3d30b962234ad9ae0b09b2d37070b3.png

http://image.zhihuishu.com/zhs/onlineexam/ueditor/201801/ae30d7c9a9be438aa2ecc5e05e2383f3.png

简支梁受载荷并取坐标系如图所示，则弯矩M，剪力Fs与分布载荷q之间的关系以及挠曲线近似微分方程为（ ）？<img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201801/138661fa31514ec18f3260ea016751ba.png" /> A: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201801/c9a73bdd6deb4aab9f9896630a771c20.png" /> B: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201801/c71656ece7e440d98230ae56ffb09033.png" /> C: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201801/d2d3cc05628d40ca87ed8b079bf4b5db.png" /> D: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201801/221b51adf2024d8ab8fdc9963e10d940.png" />

直径为d的圆截面钢杆受轴向拉力作用，已知其纵向线应变为<img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201801/767e7380667c4d688dc6c10aaf9ef9ca.png" />，弹性模量为E，给出杆轴力的四种答案，问哪一种是正确的？ A: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201801/8f37f5bc2dc94791b84f000092e493b3.png" /> B: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201801/073a4958352c4951b6171383bc4ca238.png" /> C: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201801/85f164582f934227b4bbb5ee0a7267dc.png" /> D: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201801/95e66fa0756f4ffd8c0ae368c0c88564.png" />