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Newton's Laws of Motion

Rotating Frames and Pseudo Forces

Description

Pseudo forces, also called fictitious forces, appear in a rotating frame of reference when compared with an inertial frame. They are not real forces. Instead, they are mathematical tools that help make Newton's laws of motion easier to use in a non-inertial frame. Common examples include centrifugal, Coriolis, and Eu...

Transcript

有没有想过为什么球会在旋转木马中向外飞?

当旋转木马旋转时,球会沿着一条圆形路径移动。琴弦中拉力的分量为球的圆周运动提供必要的向心力。

向心力指向圆心,由物体质量、角速度的平方和与旋转轴的距离的乘积表示。

由于球向外飞行,因此根据牛顿第三定律,向内的向心力应该具有相等且相反的向外反作用力。这种远离旋转中心的向外力称为离心力。

旋转木马中的旋转球受到离心力,将其向外推离旋转中心。

离心力是一种伪力。仅当观察系为非惯性时,才考虑它。

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