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生活中我们常常会遇到“效率”这个词,例如学习效率、工作效率等.当我们利用杠杆、斜面、滑轮等简单机械完成某项任务时,也会涉及效率的问题,我们称之为机械效率.在物理学中我们如何计算机械效率,机械效率又与哪些因素有关呢?一、认清有用功、额外功和总功要想理解机械效率,首先需要了解三个概念:有用功、额外功和总功.为达到目的必须做的功是有用功(W_有).为达到目的而不得不做的功叫额外功(W_额).
In life, we often encounter the term “efficiency”, such as learning efficiency, work efficiency, etc. When we use a simple machine such as a lever, bevel, or pulley to complete a certain task, it will also involve efficiency issues. We call it For mechanical efficiency, how do we calculate mechanical efficiency in physics, and what are the factors related to mechanical efficiency? First, recognizing useful work, extra work, and total work To understand machine efficiency, we must first understand three concepts: useful work. , extra work and total work. The work that must be done to achieve the goal is useful work (W_ ). The work that has to be done to achieve the goal is called extra work (W_ amount).