高二物理(必修加选修) 2 0 0 3年6月第1版第78页中有两个关于功与物体内能改变的演示实验:一是空气压缩引火仪演示压缩气体做功,气体内能增加;二是用图1所示的装置演示气体对外做功,内能减少.这两个演示实验操作有一定难度,要求也很高,可见度较差,效果不理想,为此,我们在图1装 Sophomore physics (compulsory plus optional) There are two demonstration experiments on energy and internal energy changes in the first edition of June 2003. The first is that the air compression priming instrument demonstrates the work done by the compressed gas, and the internal energy of the gas increases. The second is to use the device shown in Figure 1 to demonstrate the external work of the gas, and the internal energy can be reduced. The two demonstration experiments have certain difficulties, the requirements are also very high, the visibility is poor, and the effect is not ideal. For this reason, we installed in Figure 1.