A perpetual motion machine would have to be frictionless.

永动机只能是一种无摩擦力的机器。

youdao

Making energy like the sun does might too cheap to meter or as uneconomical as a perpetual motion machine.

像太阳一样产生能量可能会太便宜以至于无法计费，或是像永动机一样太不合算。

youdao

By what works in other places, I mean that this is nothing like the theory of the perpetual motion machine, which is unworkable even in principle.

他山之石，我的意思是这并不是永动机理论，这个理论在原理上本就不通。

youdao

That would that would give rise to a perpetual motion machine, breaking of the second law. It can't happen.

否则就会使,得永动机出现，打破第二定律那是不可能的。

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This creates a sort of government staffing perpetual motion machine, with agencies adding more and more headcount just to satisfy the demands of other government agencies.

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We have a perpetual motion machine of continued prosperity upwards.

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It was a perpetual motion machine that never worked.

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