声音产生与传播绝对精品.ppt

声现象 声音的产生与传播 Valadon onry. ch Asposeslides for NET 4o dient P Evaluation only. Created with Aspose Slides for NET 4.0 dient Profilo 71 Copyright 2004-2017Aspose Pty L Evaluauon onr. ch Asposeslides for NET 4o dient P Evaluation only. Created with Aspose Slides for NET 4.0 dient Profilo 71 Copyright 2004-2017Aspose Pty L 声音的产生 我们生活的世界充满了各种声音 Valadon onry. ch Asposeslides for NET 4o dient P Evaluation only. Created with Aspose Slides for NET 4.0 dient Profilo 71 Copyright 2004-2017Aspose Pty L 各种动物的声音 马叫 奇妙的声音现象 蝉叫 羊叫 公鸡打鸣嘎 虫子叫 点击喇叭播放音频 Valadon onry. ch Asposeslides for NET 4o dient P Evaluation only. Created with Aspose Slides for NET 4.0 dient Profilo 71 Copyright 2004-2017Aspose Pty L 种各样的声音 用鼠标点击不同的对象播放相应的声音 Evaluauon onr. ch Asposeslides for NET 4o dient P Evaluation only. Created with Aspose Slides for NET 4.0 dient Profilo 71 Copyright 2004-2017Aspose Pty L 探究声音是怎么产生的? 现有以下器材:桌子、直尺、橡皮筋、纸条、钢笔帽、文具 盒等器材,你能否让它们发出声音?比一比谁的方法多。 观察实验现象,得出物体发声时的共同特征是什么? Valadon onry. ch Asposeslides for NET 4o dient P Evaluation only. Created with Aspose Slides for NET 4.0 dient Profilo 71 Copyright 2004-2017Aspose Pty L 实验1:把橡皮筋拉伸到一定程度后,用手拨动 ①你听到声音了吗? ②橡皮筋在做怎样的运动? ③这声音是由什么引起的? ④当橡皮筋停止振动时,你还能听到声音吗? Valadon onry. ch Asposeslides for NET 4o dient P Evaluation only. Created with Aspose Slides for NET 4.0 dient Profilo 71 Copyright 2004-2017Aspose Pty L 实验2:用一把直尺,想办法使它发出声音,然后观察 直尺在发声时的现象,并用语言描述现象。当直尺停 止振动时,观察能否听到声音。 亲身体验:用两只手指轻轻地放在你的喉部,然后大 声喊:我们能学好物理。 ①你能感觉到喉部在振动吗? ②你知道是什么在振动吗? Valadon onry. ch Asposeslides for NET 4o dient P Evaluation only. Created with Aspose Slides for NET 4.0 dient Profilo 71 Copyright 2004-2017Aspose Pty L 结论 我们可以发现,一切发声的物体都在振动。 正在发声的物体叫声源。 Valadon onry. ch Asposeslides for NET 4o dient P Evaluation only. Created with Aspose Slides for NET 4.0 dient Profilo 71 Copyright 2004-2017Aspose Pty L 弦乐器发出声音时弦在不断振动!!! Valadon onry. ch Asposeslides for NET 4o dient P Evaluation only. Created with Aspose Slides for NET 4.0 dient Profilo 71 Copyright 2004-2017Aspose Pty