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汽车遇红灯在路口等待时,通常是不熄火的,这不但会白白消耗能源,同时还会造成环境污染.有研究显示,汽车不熄火等候10s,约需消耗汽油11mL.若在路口等候30s,消耗的汽油质量约为多少g?消耗的汽油受到重力是多少?(汽油的密度为0.8×103kg/m3
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解:1mL=1cm3,汽油的密度0.8×103kg/m3=0.8g/cm3

由ρ=

m
V
可得汽车等候10s消耗汽油质量:

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