• 2022-06-16
    真空中有一电量为Q半径为R的均匀带电球面,距离球心为r(rA: [img=58x50]1803dd6c2472b05.jpg[/img]
    B: [img=58x50]1803dd6c30022c6.jpg[/img]
    C: [img=50x50]1803dd6c3b53a5d.jpg[/img]
    D: [img=51x50]1803dd6c46d0917.jpg[/img]
  • 举一反三