发布时间:2025-01-31 13:14:44
(1)∵ρ=mV,∴水箱内水的质量:m=ρV=1.0×103kg/m3×20m3=2×104kg;(2)水的重力:G=mg=2×104kg×10N/kg=2×105N,对水做的有用功:W有用=Gh=2×105N×10m=2×106J;(3)∵η=W有用W总,∴抽水机做的总功:W总=W有用η=2×106J50%=4×106J,∵P=Wt,∴抽水的...
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