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Glite Dictionary
first law of thermodynamics

first law of thermodynamics

1 4.5
Total energy in a place where nothing enters or leaves stays the same while it changes form
  • noun
  • /fɜrst lɔː ʌv ˌθɜrməˈdɒnəmɪks/
  • Specialized
translation icon : primera ley de la termodinámica
  • As explained by the first law of thermodynamics, matter/energy cannot be created or destroyed, only transformed from one form to another.

Examples

  • According to the first law of thermodynamics, the total energy in a closed system remains constant.

  • The first law of thermodynamics states that matter and energy can be neither created nor destroyed.

    Academic text (1992)

  • Scientifically speaking, within a universe diagrammed by Newtonian mechanics, the first law of thermodynamics states that mass/energy cannot be created or destroyed.

    Blog text (5)

  • The first law of thermodynamics states that energy is neither created nor destroyed in an isolated system.

  • The first law of thermodynamics explains how energy can be transformed but never created or eliminated.

Synonyms

conservation of energy
vsfirst law of thermodynamics
  • Specialized
3 4.1

A basic physics rule that total energy in a closed system cannot be created or destroyed

is the same principle applied specifically within thermodynamics contexts
law of conservation of energy
vsfirst law of thermodynamics
  • Specialized
1 4.9

Total energy in a system that does not gain or lose energy stays the same

is the thermodynamics expression focusing on energy transformations and conservation

Surface Forms

first law of thermodynamics singular
first laws of thermodynamics plural

Morphology

first + law + of + thermodynamics

The phrase is largely compositional: 'first' (primary) + 'law' (scientific principle) + 'thermodynamics' (study of energy/heat) lets a learner infer it is an important principle about thermodynamics. However, the specific content (the conservation of energy and its technical formulation) requires subject-matter knowledge beyond B1 vocabulary, so the meaning is only partially predictable.

Etymology

First law of thermodynamics comes from early work on heat and steam engines, where people noticed that the fuel's energy did not disappear but changed into motion or stored heat. So the law is a simple rule: 'energy cannot be created or destroyed, only changed', which is why the phrase means the total energy in a system stays the same.