516969
幼苗
共回答了11个问题采纳率:90.9% 举报
一卷长1650m(1650000mm)的直径0.35mm的细线
细线半径=0.35mm÷2=0.175mm
细线体积=3.14×0.175²×1650000=158668.125mm³
1根长0.5m(500mm)直径10mm的铁棒
铁棒半径=10mm÷2=5mm
铁棒体积=3.14×5²×500=39250mm³
(不计空隙)
后缠绕而成的圆柱体体积=158668.125mm³+39250mm³=197918.125mm³
圆柱体底面积=圆柱体体积÷高=197918.125mm³÷500mm=395.83625mm²
圆柱体半径=根号(圆柱体底面积÷3.14)=根号126.0625≈11.227755786443mm
圆柱体直径=2×圆柱体半径=2×11.23=22.46mm
1年前
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