relative permittivity: meaning, definition, pronunciation and examples
C2Academic, Technical
Quick answer
What does “relative permittivity” mean?
A dimensionless number that measures how much an electric field is reduced within a material compared to a vacuum.
Audio
Pronunciation
Definition
Meaning and Definition
A dimensionless number that measures how much an electric field is reduced within a material compared to a vacuum.
In physics and engineering, it quantifies a material's ability to polarize in response to an electric field, affecting capacitance, wave propagation speed, and energy storage. It is also known as the dielectric constant.
Dialectal Variation
British vs American Usage
Differences
No significant lexical or spelling differences. The term is identical in both variants.
Connotations
None beyond its technical meaning.
Frequency
Used with equal frequency in academic physics and engineering contexts in both regions.
Grammar
How to Use “relative permittivity” in a Sentence
The relative permittivity [of + material] [is/measures/equals + value].To determine/find/calculate the relative permittivity.Vocabulary
Collocations
Examples
Examples of “relative permittivity” in a Sentence
adjective
British English
- The relative permittivity value is critical for the design.
American English
- The relative-permittivity measurement was taken at 1 kHz.
Usage
Meaning in Context
Business
Not used.
Academic
Core term in physics, materials science, and electrical engineering courses and research.
Everyday
Not used.
Technical
Essential in designing capacitors, antennas, printed circuit boards, and optical devices.
Vocabulary
Synonyms of “relative permittivity”
Vocabulary
Antonyms of “relative permittivity”
Watch out
Common Mistakes When Using “relative permittivity”
- Omitting 'relative' and just saying 'permittivity', which has different units.
- Pronouncing 'permittivity' as /pəˈmɪtɪvɪti/ (like 'permission') instead of /ˌpɜː.mɪˈtɪv.ɪ.ti/.
- Treating it as a fixed, unchangeable property for a given material.
FAQ
Frequently Asked Questions
Yes, in most contexts they are synonymous. However, 'dielectric constant' is an older term that can imply a fixed value, whereas 'relative permittivity' more accurately describes a property that can vary with frequency and temperature.
Permittivity (ε) has units (Farads per metre). Relative permittivity (ε_r) is a dimensionless ratio: the permittivity of a material divided by the permittivity of free space (ε₀).
For most common materials, it is greater than 1. In some engineered metamaterials or plasma, effective relative permittivity can be less than 1, which leads to unusual electromagnetic behaviour.
It determines the speed of signals in computer chips, the focusing power of camera lenses, the efficiency of capacitors in electronics, and how food heats in a microwave oven.
A dimensionless number that measures how much an electric field is reduced within a material compared to a vacuum.
Relative permittivity is usually academic, technical in register.
Relative permittivity: in British English it is pronounced /ˈrɛl.ə.tɪv ˌpɜː.mɪˈtɪv.ɪ.ti/, and in American English it is pronounced /ˈrɛl.ə.t̬ɪv ˌpɝː.mɪˈtɪv.ə.t̬i/. Tap the audio buttons above to hear it.
Learning
Memory Aids
Mnemonic
Think of it as a material's 'electrical sponge' rating: a high relative permittivity means it can 'soak up' more electric field than a vacuum.
Conceptual Metaphor
ELECTRIC FIELD SUPPORT IS THICKNESS; A material with high relative permittivity is like a thick, supportive mattress for an electric field.
Practice
Quiz
What is a common synonym for 'relative permittivity'?