一、实验设计实验目的:了解空气的压力实验材料:玻璃杯一个、硬纸板一块(边缘稍大于玻璃杯杯口)二、实验步骤1.把玻璃杯盛满水,尽量让水高出杯沿儿一些.2.轻轻地把硬纸板推过玻璃杯口表面,使硬纸板完全盖住玻璃杯口. First, the experimental design The purpose of the experiment: to understand the pressure of the air Experimental Materials: a glass, a piece of cardboard (edge ​​slightly larger than the glass cup mouth) Second, the experimental steps 1. The glass filled with water, 2. Gently push the cardboard through the mouth of the glass so that the cardboard completely covers the glass.