noun
torsion balance
A scientific instrument that measures small forces by the twisting of a wire or fiber. Used in physics experiments, notably by Coulomb.
クーロンはねじれ秤を使って電気力を測定した。
Coulomb measured electric force using a torsion balance.
Alternate kanji spelling using 捩 (twist); less common.
Compound of ねじれ (twist) + 秤 (scale). The exact historical derivation is uncertain; the term describes the instrument's operating principle.