permittivityn.

Brit.

/ˌpəːmᵻˈtɪvᵻti/, U.S.

/ˌpərməˈtɪvᵻdi/

Origin: Formed within English, by derivation. Etymons: permit v., -ivity suffix.

Etymology: < permit v. + -ivity suffix, perhaps after resistivity n.

Physics.

One of the physical parameters of a medium, equal to the ratio of the electric displacement D to the electric field strength E at any point in it (symbol ε, SI unit farad metre⁻¹); (also, more fully relative permittivity), the ratio of the permittivity of a medium to that of free space; = dielectric constant n. at dielectric adj. 2b; permittivity of free space n. a constant ε₀ which in the cgs electrostatic system of units is one and in the International System of Units is ¹/ _μ₀c² (= 8.854 × 10⁻¹²) farad metre⁻¹, where μ₀ is the permeability of free space and c is the speed of light.

ΘΚΠ

the world > matter > physics > electromagnetic radiation > electricity > transmission of electricity, conduction > non-conduction, insulation > [noun] > displacement > ratio of

permittance1887

permittivity1887

the world > matter > physics > electromagnetic radiation > electricity > [noun] > static electricity > constant

permittivity of free space1938

the world > matter > physics > electromagnetic radiation > electricity > transmission of electricity, conduction > non-conduction, insulation > [noun] > displacement > constant

specific inductive capacity1838

dielectric constant1875

relative permittivity1893

permittivity of free space1938

1887 O. Heaviside in Electrician 17 June 124/1 Nomenclature Scheme... Permittance. Permittivity.

1890 Electrician 14 Nov. 41 The use of the words decalescence, reluctancy, reluctivity, elastance, elastivity, permittivity, might be well deferred till they are more generally adopted.

1923 C. P. Steinmetz Four Lect. Relativity & Space ii. 23 The field energy is proportional to..the electromagnetic constants of space (permeability, or specific inductance, and permittivity, or specific capacity).

1938 G. P. Harnwell Princ. Electr. & Electromagn. i. 12 If the charges are measured in coulombs and if r is in meters and F in newtons, the constant κ₀ has the value κ₀ =..8·85 × 10⁻¹² farads/meter... This constant..is known as the permittivity of free space.

1944 London, Edinb. & Dublin Philos. Mag. 7th Ser. 35 83 Guggenheim has suggested the term permittivity for the fundamental quantity and specific inductive capacity or dielectric constant for the derived quantity. In conformity with the other suggestions in this paper it would be more uniform to adopt permittivity and relative permittivity... Similarly in the magnetic case we have permeability and relative permeability.

1946 Nature 6 July 33/2 The paper contains a description of apparatus used for measurements at frequencies of about 3,000 Mc./s...and a statement of typical experimental results obtained with a specimen of polythene, which at the above frequency had a permittivity of 2·27.

1962 D. R. Corson & P. Lorrain Introd. Electromagn. Fields ix. 317 The permittivity of free space ε₀ can..be determined directly from measurements involving electrostatic phenomena.

1974 P. K. Harvey & K. J. Bohlman Stereo F.M. Radio Handbk. vii. 148 Because of the presence of water vapour in particular, the permittivity of the air in the troposphere is greater than unity.

1997 Proc. Royal Soc. A. 453 2110 The dielectric permittivity parallel to n is approximately equal [to] or less than the perpendicular component.

This entry has been updated (OED Third Edition, December 2005; most recently modified version published online March 2022).

单词	permittivity
释义	permittivityn. Brit. /ˌpəːmᵻˈtɪvᵻti/, U.S. /ˌpərməˈtɪvᵻdi/ Origin: Formed within English, by derivation. Etymons: permit v., -ivity suffix. Etymology: < permit v. + -ivity suffix, perhaps after resistivity n. Physics. One of the physical parameters of a medium, equal to the ratio of the electric displacement D to the electric field strength E at any point in it (symbol ε, SI unit farad metre⁻¹); (also, more fully relative permittivity), the ratio of the permittivity of a medium to that of free space; = dielectric constant n. at dielectric adj. 2b; permittivity of free space n. a constant ε₀ which in the cgs electrostatic system of units is one and in the International System of Units is ¹/ _μ₀c² (= 8.854 × 10⁻¹²) farad metre⁻¹, where μ₀ is the permeability of free space and c is the speed of light. ΘΚΠ the world > matter > physics > electromagnetic radiation > electricity > transmission of electricity, conduction > non-conduction, insulation > [noun] > displacement > ratio of permittance1887 permittivity1887 the world > matter > physics > electromagnetic radiation > electricity > [noun] > static electricity > constant permittivity of free space1938 the world > matter > physics > electromagnetic radiation > electricity > transmission of electricity, conduction > non-conduction, insulation > [noun] > displacement > constant specific inductive capacity1838 dielectric constant1875 relative permittivity1893 permittivity of free space1938 1887 O. Heaviside in Electrician 17 June 124/1 Nomenclature Scheme... Permittance. Permittivity. 1890 Electrician 14 Nov. 41 The use of the words decalescence, reluctancy, reluctivity, elastance, elastivity, permittivity, might be well deferred till they are more generally adopted. 1923 C. P. Steinmetz Four Lect. Relativity & Space ii. 23 The field energy is proportional to..the electromagnetic constants of space (permeability, or specific inductance, and permittivity, or specific capacity). 1938 G. P. Harnwell Princ. Electr. & Electromagn. i. 12 If the charges are measured in coulombs and if r is in meters and F in newtons, the constant κ₀ has the value κ₀ =..8·85 × 10⁻¹² farads/meter... This constant..is known as the permittivity of free space. 1944 London, Edinb. & Dublin Philos. Mag. 7th Ser. 35 83 Guggenheim has suggested the term permittivity for the fundamental quantity and specific inductive capacity or dielectric constant for the derived quantity. In conformity with the other suggestions in this paper it would be more uniform to adopt permittivity and relative permittivity... Similarly in the magnetic case we have permeability and relative permeability. 1946 Nature 6 July 33/2 The paper contains a description of apparatus used for measurements at frequencies of about 3,000 Mc./s...and a statement of typical experimental results obtained with a specimen of polythene, which at the above frequency had a permittivity of 2·27. 1962 D. R. Corson & P. Lorrain Introd. Electromagn. Fields ix. 317 The permittivity of free space ε₀ can..be determined directly from measurements involving electrostatic phenomena. 1974 P. K. Harvey & K. J. Bohlman Stereo F.M. Radio Handbk. vii. 148 Because of the presence of water vapour in particular, the permittivity of the air in the troposphere is greater than unity. 1997 Proc. Royal Soc. A. 453 2110 The dielectric permittivity parallel to n is approximately equal [to] or less than the perpendicular component. This entry has been updated (OED Third Edition, December 2005; most recently modified version published online March 2022). < n.1887
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