Zero method

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[Measurement method]
When measuring the mass of an object with a balance, the object is placed on one pan and several weights are placed on the other pan. When the lever is balanced horizontally, the sum of the weights gives the mass of the object. This method of comparing the same kind of physical quantity that can be changed arbitrarily with respect to the quantity being measured, and adjusting the difference between the two to zero, and taking the value of the adjusted quantity as the measured value, is called the zero method. In contrast, the method of reading a physical quantity that changes according to the quantity being measured, such as a mercury thermometer or voltmeter, on a scale is called the deflection method.

*Some of the terminology explanations that mention "zero method" are listed below.

Source | Heibonsha World Encyclopedia 2nd Edition | Information

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［測定の方法］
　てんびんで物体の質量を測るときは，一方の皿にその物体を載せ，他方の皿にいくつかの分銅を載せててこが水平に平衡したときの分銅の質量の総和で物体の質量を知る。このように測定量に対して任意に変えられる同種の物理量を用意して比較し，両者の差が零になるように調整したときの，その調整した量の値をもって測定値とする方法を零位法zero methodという。これに対して，水銀温度計や電圧計のように測定量に応じて変化する物理量を目盛で読み取る方法を偏位法deflection methodという。…

※「zero method」について言及している用語解説の一部を掲載しています。

出典｜株式会社平凡社世界大百科事典 第２版について | 情報