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振动和波. 物理教研室. 振动与波基本理论 第一节 振动 机械振动 定义 :物体在一定位置附近作往复的运动。. 机械振动的动力学特征: 受有回复力和惯性的交互作用。. 一、 简谐振动. 结论 : 简谐振动的位移、速度和加速度都是随时间作周期性变化的。. 二、 简谐振动的图像. 简谐振动的特征量 : 1 、振幅 2 、周期 3 、初相位. 三、阻尼振动(减幅振动) 定义: 振幅随时间减小的振动。.

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物理教研室

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