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Glite Dictionary
adiabatic index

adiabatic index

9.9
A number comparing how much heat a gas holds at fixed pressure and fixed volume
  • noun
  • /ˌeɪdiˈæbətɪk ˈɪndɛks/
  • Specialized
translation icon : índice adiabático
  • The adiabatic index for air is approximately 1.4.

Examples

  • The adiabatic index for an ideal monoatomic gas is typically 5/3.

  • The change in pressure and temperature during compression can be predicted using the adiabatic index.

  • Understanding the adiabatic index is essential in calculations of engine efficiency.

  • What is the adiabatic index of carbon dioxide?

  • The adiabatic index of helium is about 1.67, which makes it a good choice for certain astrological applications.

  • Scientists often use the adiabatic index to determine the behavior of gases under rapid compression.

  • For many gases, the adiabatic index is crucial for calculating changes in temperature and pressure.

Synonyms

heat capacity ratio
vsadiabatic index
  • Specialized
7.0

The number showing how much more heat a material needs at constant pressure than at constant volume

applies specifically to gases and is commonly denoted by the name gamma

Surface Forms

adiabatic index singular
adiabatic indices plural

Morphology

adiabatic + index

The phrase is compositionally built from 'adiabatic' (no heat transfer) and 'index' (a numeric indicator), so a learner who knows both words would infer it refers to a numerical parameter related to adiabatic processes. However, the precise technical meaning (the specific ratio of heat capacities, γ = cp/cv) requires domain knowledge beyond constituent meanings, making it only partially predictable.

Etymology

Adiabatic index combines adiabatic and index: adiabatic describes a change where 'no heat goes in or out', and index means a 'number that compares two things'. So the adiabatic index is the single number that tells how a gas's pressure and temperature change when it is squeezed or allowed to expand without heat entering or leaving.