如图所示，无限长直导线在 P处弯成半径为R 的圆，当通以电流I 时，则在圆心O点的磁感强度大小等于http://image.zhihuishu.com/zhs/onlineexam/ueditor/201902/ff6cdd164782462491b9cbca5a6ebb8e.PNG

2021-04-14

答案：

http://image.zhihuishu.com/zhs/onlineexam/ueditor/201902/cd30626bb2c84f1f9f7616b2bce8f196.PNG

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无限长直导线在P处弯成半径为R的圆，当通以电流I时，则在圆心O点的磁感强度大小等于<img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201909/247132caa86643248801a9ce73153643.png" /> A: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201909/d6ca935b43b5409982580c397b20452a.png" /> B: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201909/05df5ede8d854c86adb4aa49ab7d213a.png" /> C: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201909/fd586a02dd0d48d2a9d8451722bd0cc8.png" /> D: 0 E: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201909/5b15cee769754f5b8d999d9c5bb28961.png" />
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无限长直导线在P处弯成半径为R的圆，当通以电流I时，则在圆心O点的磁感强度大小等于[img=135x93]17d60751bdceb2e.png[/img] 未知类型：{'options': ['', '', '', '0', ''], 'type': 102}
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无限长直导线在P处弯成半径为 R 的圆，当通以电流I时，则在圆心O点的磁感强度大小等于（）。[img=179x114]17d6056152f4661.png[/img] 未知类型：{'options': ['', '0', '', ''], 'type': 102}
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无限长直导线在P处弯成半径为R的圆，当通以电流I时，则在圆心O点的磁感应强度大小等于（）。 A: B: C: 0 D: E:
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无限长直导线在P处弯成半径为R的圆，当通以电流I时，则圆心O点的磁感应强度B的大小等