一捆细铜线质量为44.5kg,截面积为25mm,求这捆细铜线的长度（铜的密度为8.9×10³kg/m
问题描述：
一捆细铜线质量为44.5kg,截面积为25mm,求这捆细铜线的长度（铜的密度为8.9×10³kg/m
答
V=M/P
=44.5kg/8.9*10^3kg/m^3
=0.005m^3
=5000000mm^3
长度=5000000mm^3/25mm^2
=200000mm
=200m