物理学中包括许多种力,让学生头痛的力不少,要说最让学生头痛的,相信大多选答案——摩擦力.在摩擦力的相关知识中,摩擦力做功的情况比较复杂,有时做正功,有时做负功,还有时与其他能量之间发生转移.一、摩擦力可以做正功、负功和不做功摩擦力对物体做正功、负功和不做功,可以根据功的定义式W=F·scosα来判断,这是我们必须要掌握的方法,也是最基本的方法.若摩擦力和位移的夹角0°≤α<90°,则该力做正 Physics, including many kinds of power, so that students have a lot of headaches, to say that the most students headache, I believe most of the answers - friction. In the friction related knowledge, the friction work is more complex, and sometimes Do positive work, sometimes do negative work, sometimes with the transfer of other energy.First, the friction can do positive work, negative work and not work friction to do positive work, negative work and not work, you can work The definition of W = F · scosα to determine, which is that we have to master the method is the most basic method if the friction and displacement of the angle 0 ° ≤ α <90 °, the force is positive