One is inertial mass, which is how much you hate your velocity to change, how hard you resist acceleration.

一个是惯性质量,它反映了物体速度改变的难易程度,即保持加速度的难易程度

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As a feature of social networks, critical mass is hard to overvalue.

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That's why he fought so hard for Medicare, for mass transit and the minimum wage, for civil rights and women's rights.

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The corporate chief simply pushes his "automatic flight mode" and the plane will glide nicely as the mass will work hard to set the course.

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