中学生使用斜面小车做验证牛顿第二定律的实验时,由于摩擦阻力的存在,不得不考虑用一种方法来克服它。一般是将斜面不带滑轮的一端垫高,使小车在斜面上能作匀速运动,即用小车下滑力来平衡摩擦阻力(包括纸带及打点所产生的阻力)。这个摩擦阻力究竟有多大?一种方法是将斜面放置水平,然后加砝码测小车作匀速运动所需要的力,即为摩擦阻力。下面介绍用回归法测摩擦阻力,供参考。 Middle school students using a beveled car to verify Newton’s second law experiment, due to the existence of frictional resistance, had to consider a way to overcome it. Generally, one side of the inclined plane without the pulley is lifted so that the car can move at a constant speed on the inclined plane, that is, the sliding resistance of the car is used to balance the frictional resistance (including the resistance caused by the paper band and the punching point). This frictional resistance how much? One way is to place the bevel level, and then add the weight of the car to measure the force required for uniform movement, is the frictional resistance. The following describes the regression method to measure friction resistance for reference.