• 2022-07-01
    已知环形截面外径为D,内径为d,则截面对形心的极惯性矩( )
    A: [img=124x69]18037cad239f72c.png[/img]
    B: [img=132x73]18037cad2ec6b42.png[/img]
    C: [img=120x66]18037cad39b2590.png[/img]
    D: [img=125x70]18037cad44fedf9.png[/img]