• 2022-05-27
    ‏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=105x81]1803dbaac625546.gif[/img]‎
    A: [img=33x44]1803dbaacfb935a.png[/img]
    B: [img=26x44]1803dbaad80d921.png[/img]
    C: [img=77x44]1803dbaadfb0da2.png[/img]
    D: [img=83x44]1803dbaae83ad97.png[/img]
  • 举一反三