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我们生活在充满声音的世界里:春天的花园里,好鸟相鸣,嘤嘤成韵;舞台上,演奏者利用手中的乐器奏出动人的旋律;课堂上,师生之间通过声音交流学习;马路上,各种车辆声此起彼伏.那么声音是怎样产生的?又是怎样传播的呢?考点1:声音是怎样产生的声音是由物体振动产生的,一切正在发声的物体都在振动.比如,当你说话时,声带在振动;用力拨动吉他的琴弦使其发声时,琴弦在振动;在桌子上放些绿豆,用力拍打桌面,可以看到绿豆在跳动,说明桌面在振动.
We live in a world filled with sounds: in the spring garden, good birds meet and grow into rhyme; on the stage, performers use their musical instruments to make moving melodies; in classes, students and students exchange their voices through sound ; On the road, a variety of vehicles sound one after another.So how the sound is produced? And how is it spread? Test 1: The sound is how the sound is generated by the object vibration, all sound objects are vibrating. When you speak, the vocal cords are vibrating. When the strings of a guitar are struck, the strings vibrate. Put some mung beans on the table and forcefully tap the tabletop to see that the mung beans are beating, indicating that the table is vibrating.