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问题 填空题

金属铝的密度为2.7×103kg/m3一铝锭的质量为5.4kg，这个铝锭的体积为______；若用此铝锭制成一个空心球，它的质量______5.4kg（选填“大于”、“等于”、或“小于”）．

答案

根据ρ=

m
V
可得，铝锭的体积：

V=

m
ρ
=
5.4kg
2.7×103kg/m3
=2×10-3m3；

用此铝锭制成一个空心球时，球的质量为5.4kg．

故答案为：2×10-3m3；等于．

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