• 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]180361a1a4ffe5d.png[/img]
    A: [img=33x44]180361a1ac986f4.png[/img]
    B: [img=26x44]180361a1b7cf5b2.png[/img]
    C: [img=77x44]180361a1c0c28d3.png[/img]
    D: [img=83x44]180361a1cb490b7.png[/img]
  • 举一反三