如图所示为内燃机的能流图，则内燃机的效率可表示为_刷题宝

题干

如图所示为内燃机的能流图，则内燃机的效率可表示为（　　）

A：η= $\frac{E_{1} + E_{2} + E_{3} + E_{4}}{E}$ ×100%

B：η= $\frac{E_{1} + E_{2} + E_{3}}{E}$ ×100%

C：η= $\frac{E_{2}}{E}$ ×100%

D：η= $\frac{E_{1}}{E}$ ×100%

上一题下一题 0.0难度选择题更新时间:2012-04-24 05:13:16

答案(点此获取答案解析）

C

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