笔和纸是每个学生必备的文具。利用它们的组合,可以做一些中学物理实验,现介绍如下。一、模拟相对运动在一张白纸上画上云、树、房屋、……,在它面前竖放一枝笔,模拟火箭。当白纸竖直向下运动时,可以产生“火箭’渐渐上升的印象。二、滑动摩擦力与滚动摩擦力大小比较 Pen and paper are essential stationery for every student. Using their combination, you can do some middle school physics experiments, which are described below. 1. Simulate relative motions. Draw clouds, trees, houses,... on a white paper, put a pen in front of it, and simulate the rocket. When the white paper moves vertically downwards, it can give rise to the ”rocket" gradually rising impression.Second, the comparison of sliding friction force and rolling friction force size