关于空气有质量的演示实验,对学生理解大气压的存在是很有意义的,实践证明也是很有必要性的。刘平权老师在《物理教学探讨》杂志上曾发表文章,介绍了如下方法:调节天平,往玩具气球中吹入一部分气体,将口扎紧放在天平的左盘中,在右盘加砝码使天平平衡。然后放去气球内的气体,天平就失去平衡,这说明了气体有质量。笔者对这样使用玩具气球来演示空气有质量,觉得其科学性有必要进行探讨,今提出来与大家商讨。 Demonstration experiments on the quality of air are very meaningful for students to understand the existence of atmospheric pressure, and practice has proved very necessary. Professor Liu Pingquan published an article in the “Physical Teaching Discussion” magazine and introduced the following methods: Adjust the balance, blow a part of the gas into the toy balloon, and tie the mouth tightly in the left plate of the balance. Add weights on the right side. Balance the balance. Then let go of the gas in the balloon and the balance will lose its balance. This shows that the gas has quality. The author used this toy balloon to demonstrate the quality of the air, and felt that it was necessary to discuss the scientific nature of the air. I would like to discuss with you today.