conservation of mass

American  

noun

Physics.

1. the principle that in any closed system subjected to no external forces, the mass is constant irrespective of its changes in form; the principle that matter cannot be created or destroyed.

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conservation of mass British  

noun

1. the principle that the total mass of any isolated system is constant and is independent of any chemical and physical changes taking place within the system

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conservation of mass Scientific  

1. A principle of classical physics stating that the total mass of a closed system is unchanged by interaction of its parts. The principle does not hold under Special Relativity, since mass and energy can be converted into one another.

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Etymology

Origin of conservation of mass

First recorded in 1880–85

Example Sentences

The shape-shifting transfiguration spells in J. K. Rowling’s Harry Potter series, for instance, pose problems related to conservation of mass.

From Nature • Oct. 14, 2019

I used to think being friends with an ex was a decent idea, like it established a certain level of maturity between two former partners while also confirming the law of conservation of mass.

From Salon • May 12, 2016

This is because chemical reactions are governed by the law of conservation of mass, which states that matter cannot be created or destroyed in a chemical reaction.

From Textbooks • Jun. 19, 2013

This is called “the conservation of mass and energy”.

From Scientific American • Dec. 6, 2012

This became known as the conservation of mass, and it was a revolutionary concept.

From "A Short History of Nearly Everything" by Bill Bryson