我们的地球被几百千米厚的大气层包围着,大气由于受到重力的作用而产生大气压．大气压无处不在,一个中学生身体表面积若按1m2计算,则身体表面要承受1×105N的压力,这相当于200个中学生的体重．但由于人体内外的压强相平衡的缘故,我们深受“重压”却全然不觉,也正是这个原因,我们常常忽略了大气压的存在． Our Earth is surrounded by a few hundred kilometers of atmosphere, and the atmosphere generates atmospheric pressure due to gravity. Atmospheric pressure is everywhere. If a student’s body surface area is calculated at 1m2, the body surface should bear a pressure of 1×105N, which is equivalent to the weight of 200 middle school students. However, due to the balance of pressure inside and outside the human body, we are deeply unaware of the “heavy pressure”. This is also the reason. We often neglect the existence of atmospheric pressure.