Well, if we just take, for example, MgO, and let's try Mg, magnesium chloride just as an example.

我们以MgO为例，让我们试试Mg，MgCl2也是一个例。

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Therefore, it'll compress by an unknown x, which is equal to mg divided by the force constant of the spring.

因此它的压缩量为 x,也就等于 mg 除以弹簧的弹性系数

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When I was not accelerating and everything was at rest, ma was 0, w was mg, and w was the reading on the needle.

当我还没有加速,一切静止的时候,ma 是 0,w 就等于 mg,w 就是指针的读数

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So a will be negative and w, in fact, will be less than mg.

那么 a 就会变负,w 事实上就会比 mg 小

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You are pushing down with the weight mg, and the floor has got to be pushing up with the mg, because the spring is not going anywhere.

你向下的作用力是重力 mg,然后地面向上的支持力也是 mg,因为弹簧现在根本没动

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So the spring is being pushed by mg here and mg here.

所以弹簧受到一个向下的 mg 还有一个向上的 mg

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I know this is the right answer, because if I now find the acceleration, I find it's mg divided by m and I get -g as the answer for all bodies.

我知道这个等式是正确的,因为现在如果我要求物体的加速度,用 mg 除以 m,我就得到 -g,这个结果对所有物体都成立

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