Mass (m) is the quantity of matter contained in a particle or body regardless of its location in the universe. Mass is constant, whereas weight is affected by the distance of a body from the centre of the Earth (or of other planet). The SI unit is kilogram.
According to the Einstein equation
all forms of energy possess a mass equivalent.
Generalic, Eni. "Mass." Croatian-English Chemistry Dictionary & Glossary. 29 June 2022. KTF-Split. 1 Apr. 2025. <https://glossary.periodni.com>.
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