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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.


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

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

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.


Etymology

Origin of conservation of mass

First recorded in 1880–85

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

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

From Literature

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

“What about the law of conservation of mass, as stated by the 18th-century French chemist Antoine Lavoisier, which holds that mass can neither be created nor destroyed?”

From New York Times

This study basically examines light as a molecule, bound states, the strong interaction, the conservation of mass and energy,and the interaction between light and matter.

From Scientific American

To “conserve” something means to “save something” In the law of the conservation of mass and energy; mass and energy are not created or destroyed.

From Scientific American