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Charles's law

Charles's law

1 5.7
The volume of a gas at constant pressure increases as its temperature rises
  • noun
  • /ˈʧɑrlzɪz lɔ/
  • Specialized
: ley de Charles
  • According to Charles's law, the volume of a gas increases as its temperature rises, provided the pressure is constant.

Examples

  • A hot air balloon rises because Charles's law causes the air inside the balloon to expand when heated.

  • According to Charles's law, the volume of an ideal gas increases directly with its absolute temperature when the pressure is held constant.

  • When explaining gas behavior, teachers often refer to Charles's law alongside Boyle's law.

  • According to Charles's law, gas expands when heated.

  • Have you heard about Charles's law in your physics class?

  • A hot air balloon rises because Charles's law explains how the air inside the balloon expands as it gets hotter.

  • In thermodynamics, students learn that Charles's law illustrates the relationship between gas volume and temperature at constant pressure.

Synonyms

law of volumes
vsCharles's law
  • Specialized
1 6.2

When pressure stays the same, a gas gets bigger as its temperature rises

describes volume increasing as temperature rises at constant pressure

Surface Forms

Charles's law singular

Morphology

Charles's + law

The phrase is a possessive proper name plus 'law'; knowing 'law' only signals a scientific rule but the surname 'Charles's' carries no semantic information about gases or temperature to a learner. A B1 learner who knows the constituents would not be able to derive the specific content (volume–temperature relation) from the parts, so the expression is idiomatic in being eponymous rather than compositional.

Etymology

Charles's law is named after the French scientist Jacques Charles, who worked with hot air balloons and saw that warming the air makes the balloon grow. He noticed that when the air inside a balloon gets warmer it takes up more space, so Charles's law means 'the volume of a gas grows as temperature goes up'.