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Physics

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Oscillations

Energy Loss in Oscillations

Description

Oscillations in the real world often lose energy as they move. A system that keeps the same amplitude without any loss is called undamped. That kind of motion is rare, because friction and other non-conservative forces usually reduce the motion over time.

Common examples show this clearly. A guit...

Transcript

当一根漂浮在水面上的木头被向下推压后释放,使其上下浮动时,它会围绕其平衡位置以类似于简谐运动的恒定振幅振荡。

随着时间的推移,水施加的一种称为阻尼力的耗散力会因运动导致部分能量损失,从而减小振动的振幅,产生阻尼谐振荡。

阻尼力与原木的速度成正比,该速度用于衡量振荡衰减,其方向与运动方向相反。

合力等于恢复力和阻尼力,这两种力方向相反。

将速度和加速度方程重新整理并改写为位置对时间的导数形式,可得到一个微分二次方程,该方程描述了木块的阻尼谐振运动。