“效率”与“功率”是初中物理中两个“形似”的概念 ,大多同学不能正确划分。从以下两个方面进行辨析 ,能收到较好的效果。1　辨析三个“效率”初中物理中出现了三个“效率” ,它们是机械效率、热机效率、炉子的效率。其区别是 :机械效率是指各种机械在做功时 ,所做的有用功和 “Efficiency” and “power” are the two “similar” concepts in junior high school physics. Most students cannot be divided correctly. Discerning from the following two aspects can receive better results. 1 There are three “efficiency” in the three “efficiency” junior high school physics. They are mechanical efficiency, thermal efficiency, and furnace efficiency. The difference is: Mechanical efficiency refers to the useful work done by various machines when doing work.