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砝碼介紹

作者:  時間:2018-07-05 14:45:28  點擊數:

天平上作為質量標準的物體,通常為金屬塊或金屬片,可以稱量較精確的質量。 中國在夏代即出現相當于砝碼的“權”。此后的4000多年間,不同朝代有不同形狀和材質的“權”作為衡量的量具。在現代質量計量中,砝碼是質量量值傳遞的標準量具。質量量值以保存在法國國際計量局的鉑銥合金千克原器實物為唯一基準器。各國均將砝碼分為國家千克基準、國家千克副基準、千克工作基準,以及由千克的倍量和分量構成的工作基準組和各等工作標準砝碼

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