conservation of energy

American  

noun

Physics.

1. the principle that in a system that does not undergo any force from outside the system, the amount of energy is constant, irrespective of its changes in form.

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conservation of energy British  

noun

1. the principle that the total energy of any isolated system is constant and independent of any changes occurring within the system

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conservation of energy Scientific  

1. A principle stating that the total energy of a closed system remains constant over time, regardless of other possible changes within the system. It is related to the symmetry of time invariance.

2. See also invariance thermodynamics

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Etymology

Origin of conservation of energy

First recorded in 1850–55

Example Sentences

“There’s no conservation of energy on that end of the floor. He’s played elite defense now for a while.”

From Los Angeles Times • Feb. 27, 2025

This in turn has some important implications for the conservation of energy and momentum.

From Science Daily • Oct. 20, 2023

Because bipedalism allows for greater conservation of energy, not to mention freeing up our arms to carry tools, some anthropologists believe this behavior contributed to our brain size.

From Salon • Dec. 23, 2022

Calls for better conservation of energy are also growing in France, like in much of Europe, as the war in Ukraine squeezes supplies of gas and oil.

From New York Times • Aug. 25, 2022

Thus the universe can double the amount of positive matter energy and also double the negative gravitational energy without violation of the conservation of energy.

From "A Brief History of Time: And Other Essays" by Stephen Hawking