Then he fastened a small metallic ball on each end of the steel bar.

然后，在细钢棍的两端，各固定一个小的金属球。

youdao

The point: that a period of a pendulum is independent of the mass - the steel ball, plus one professor - hanging from it.

目的是证明：钟摆周期和质量无关—那个铁球的，以及挂在上面的那个物理教授的。

youdao

In another lecture on pendulums, he stands back against the wall, holding a steel ball at the end of a pendulum just beneath his chin.

在另外一节钟摆课上，他背靠墙站着，抓着钟摆末端的铁球，紧贴着他的下巴。

youdao

Inside there are just three stainless-steel ball bearings, housed in anodized aluminum bar stock.

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In scientific terms, it was akin to rolling a steel ball down an inclined plane to measure its velocity only to watch the ball float into the air instead.

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