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功率和机械效率是初中物理中两个重要的物理概念.初学者极易把它们混为一谈.两者的区别主要有以下几个方面:1.物理意义不同.功率指的是物体单位时间内所做的功.机械效率指的是使用机械所做的有用功跟总功的比值.2.表述对象不同.功率是用来表示物体做功快慢的物理量.机械效率是衡量机械本身性能优劣的一个重要因素.3.计算公式不同.功率的大小用公式P=W/t来计算,单位是瓦特;功率的值没有确切的范围.而机械效率用公式η=W_有/W_总来计算,它的大小通常用百分数来表
Power and mechanical efficiency are two important physics concepts in junior middle school physics, and beginners can easily confuse them with each other.The main differences between the two are as follows: 1. Physical meaning is different.Power refers to what the object does in unit time Of the mechanical efficiency refers to the use of machinery to do useful work with the total work of the ratio .2 expression of the object is different.Power is used to express the body doing work quickly and slow physical quantity.Mechanical efficiency is a measure of the merits of the mechanical performance is an important Factor .3 different calculation formula. The size of the power is calculated using the formula P = W / t, the unit is watts; the value of the power is not the exact range, while the mechanical efficiency is calculated using the formula η = W_W / Its size is usually expressed as a percentage