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目前,中学物理教学使用的声传播演示仪22007存在以下问题:一是声传播演示仪22007的说明书介绍说:“演示真空不能传声时,当用抽气机对传播筒进行抽气后,喇叭发出的声音明显减小,如果能将传播筒内抽至完全真空,则受声器就收不到声音了,从而证明真空不能传播声音。”这个推理存在以下错误:首先,即使将传播筒内抽至完全真空,如果受声器收不到声音,在证明真空不能传声的同时,是不是也应同时证明支撑发声体、
At present, the middle school physics teaching using the sound propagation demonstrator 22007 has the following problems: First, the sound propagation demonstrator 22007 manual said: “Demonstration of vacuum can not sound, when the suction tube with the suction machine after pumping, The sound from the horn is significantly reduced, and if the pod can be evacuated to full vacuum, the sound receiver can not hear the sound, thus proving that the vacuum can not propagate the sound. ”This reasoning has the following error: First of all, Tube pumping to a complete vacuum, if the sound received by the sound, the vacuum can not prove the sound at the same time, it should not also be supported at the same time supporting the sound body,