题干

如图所示,质量为2.5千克,底面积为2×1022的薄壁柱形容器(容器足够高)放置在水平地面上.另有一正方体物块A,其体积为1×1033

(1)求薄壁柱形容器对水平地面的压强.

(2)现将物块A放入容器中,再向容器中注入水,当水的体积为2×1033时,容器对地面的压强刚好等于水对容器底部压强的两倍,求物块A的质量.

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答案(点此获取答案解析)

解:(1)薄壁柱形容器对水平地面的压力:F=G=mg=2.5kg×9.8N/kg=24.5N,对水平地面的压强:p=
F
S
=24.5N

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