• 2022-05-27
    如图,一无限长直导线在某处弯成半径为R的圆。当通以电流I时,圆心O处的磁感应强度的大小为:[img=200x134]1803292605ec4ea.png[/img]
    A: [img=33x44]180329260d7109f.png[/img]
    B: [img=26x44]1803292614cafa5.png[/img]
    C: [img=77x44]180329261cd7af8.png[/img]
    D: [img=83x44]18032926242f118.png[/img]
  • 举一反三