71.如图示，在半径为R的无限长圆柱面上通有电流I （圆柱面内真空），电流I 均匀分布且方向与圆柱面的轴平行，柱面外一矩形线框与柱面的轴线共面，位置如图。下列说法正确的是（ ）A: 如果圆柱面上的电流发生变化，圆柱面内的磁感应强度分布也会发生变化
B: 通过矩形线框包围面积上的磁通量
C: 当圆柱面上的电流以
的变化率均匀增大时，线框中无感应电动势D: 圆柱面外的磁感应强度分布
举一反三
- 铝合金拉伸实验的MOOC中，需要测试性能指标（ ） A: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202011/418dff8a904f4789899ce32e4cd03b74.png" />、<img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202011/411578dcfdda41a3bc8821b9bfb1d916.png" />、<img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202011/806ea04e59cd436faec9f7992d126ee5.png" />与<img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202011/61011c7d884349459d41d9f3670d7d0e.png" /> B: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202011/57ab5cc8b9dd4fb0961726058a6e9c52.png" />、<img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202011/806ea04e59cd436faec9f7992d126ee5.png" />与<img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202011/61011c7d884349459d41d9f3670d7d0e.png" /> C: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202011/32ff0f454bde4334ae385089a853b9ac.png" />、<img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202011/ab0315aab0fa4918a53714026df50fa3.png" />、<img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202011/806ea04e59cd436faec9f7992d126ee5.png" />与<img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202011/61011c7d884349459d41d9f3670d7d0e.png" />
- 17d60db40343ba7.png71.如图示，在半径为R的无限长圆柱面上通有电流I （圆柱面内真空），电流I 均匀分布且方向与圆柱面的轴平行，柱面外一矩形线框与柱面的轴线共面，位置如图。下列说法正确的是（ ） 未知类型：{'options': ['如果圆柱面上的电流发生变化，圆柱面内的磁感应强度分布也会发生变化', '通过矩形线框包围面积上的磁通量[img=272x165]17d60db4144e72a.png[/img]', '当圆柱面上的电流以[img=89x164]17d60db42515935.png[/img]的变化率均匀增大时，线框中无感应电动势', '圆柱面外的磁感应强度分布[img=264x192]17d60db43586b8f.png[/img]'], 'type': 102}
- 铸铁拉伸实验的MOOC中，需要测试性能指标（ ） A: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202011/53667f9a659c4652a1d73a3dd36986bf.png" /> B: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202011/875d968dec834cdfa4c3fe247d7aa2a8.png" />、<img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202011/5d8957af2d2a4f51819415939c6345f0.png" /> C: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202011/b636e1e0d6a94025871bb57705cf25bd.png" />、<img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202011/6219f1e929704d49b7379c136363c22b.png" />、<img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202011/b542e12f707949e0a011640e81330eea.png" />与<img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202011/68fe4ce598db473387b30de3c218f70c.png" />
- <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202011/052081f78b734e3d9cb762ec9a498ff0.png" />69.如图所示，一中空的无限长圆柱形导体壳层（<img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202011/d05cde406fcf427991cf931c89d700ec.png" />区域是空的），导体的内外半径分别为 a 和 b 。设导体内平行于轴线方向上通有电流 I ，且电流均匀分布在导体的横截面上。若 r 为离开导体轴线的距离，下列说法正确的是（ ） A: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202011/795f791319374ec1a99675dcf97c4bd6.png" />区域的磁感应强度<img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202011/76c3687faa674bfca0a28dc521ef022d.png" /> B: 导体横截面上电流密度大小为<img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202011/6b24f37b663d49fdac38a06d257c7ebf.png" /> C: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202011/d05cde406fcf427991cf931c89d700ec.png" />区域的磁感应强度<img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202011/d9343d6603034a18a1402d79e39534e7.png" /> D: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202011/54f37f9ca2dd422da5a79a1754492564.png" />区域的磁感应强度<img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202011/069097119b8441328933c47f6cb53988.png" />
- 判定系数<img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202011/884048ab090f4001856b6b5be7ce702d.png" />可表示为( )。 A: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202011/595552013f6f4712972e25f5205785e3.png" /> B: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202011/448d29a283a1437e972417c64c9186ba.png" /> C: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202011/0757164fbffa45a7afd4984db734d818.png" /> D: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202011/c804edbb8d30463a9074d63b355031d0.png" />