radiometer
lowtechnical / scientific
Definition
Meaning
A scientific instrument for detecting and measuring radiant energy, often using vanes that rotate when exposed to light or heat.
A device that detects or measures electromagnetic radiation, such as light, infrared, or microwave radiation. The most common type, the Crookes radiometer, consists of a set of vanes inside a partial vacuum that rotate when light shines on them.
Linguistics
Semantic Notes
In a scientific context, 'radiometer' is a general term for radiation-measuring instruments. In everyday contexts, it is often associated with the decorative Crookes radiometer 'light mill', popular as a scientific curiosity or desk ornament.
Dialectal Variation
British vs American Usage
Differences
No significant difference in usage or meaning. Spelling is consistent.
Connotations
Neutral technical term in both varieties.
Frequency
Equally low-frequency in both scientific and general discourse.
Vocabulary
Collocations
Grammar
Valency Patterns
The [type] radiometer measures [phenomenon].Scientists used a radiometer to [purpose].A radiometer consists of [components].Vocabulary
Synonyms
Strong
Neutral
Weak
Vocabulary
Antonyms
Phrases
Idioms & Phrases
- “No common idioms use this word.”
Usage
Context Usage
Business
Rare, potentially in the context of manufacturing or selling scientific instruments.
Academic
Common in physics, meteorology, remote sensing, and engineering papers discussing measurement of radiation.
Everyday
Rare, primarily encountered as a decorative novelty item (the spinning Crookes radiometer).
Technical
Standard term for instruments measuring radiant flux or power of electromagnetic radiation.
Examples
By Part of Speech
adjective
British English
- The radiometric data was crucial.
- They performed a radiometric analysis.
American English
- The radiometric data was crucial.
- They performed a radiometric analysis.
Examples
By CEFR Level
- The glass radiometer spins in the sunlight.
- He has a small radiometer on his desk.
- The scientist explained how the radiometer's vanes move.
- A radiometer can measure the strength of light.
- Meteorological satellites use advanced radiometers to monitor sea surface temperatures.
- The calibration of the microwave radiometer was essential for accurate data collection.
- Differential absorption measurements from the limb-sounding radiometer allowed for precise profiling of atmospheric constituents.
- The team's research hinged on the novel application of a heterodyne radiometer in the submillimetre wave band.
Learning
Memory Aids
Mnemonic
Think: RADIO (as in radiation) + METER (as in measuring device). A meter for measuring radiated energy.
Conceptual Metaphor
None dominant.
Watch out
Common Pitfalls
Translation Traps (for Russian speakers)
- Do not confuse with 'радиометр' which can also refer to a 'radiation survey meter' (for radioactivity).
- The decorative spinning 'light mill' is often simply called 'radiometer' in English, which may be narrower than the Russian use.
Common Mistakes
- Misspelling as 'radiometre' (non-standard).
- Confusing it with a 'Geiger counter' (which measures ionising radiation).
- Pronouncing it /ˈreɪ.di.oʊˌmiː.tɚ/ (incorrect stress).
Practice
Quiz
What typically causes the vanes of a Crookes radiometer to spin?
FAQ
Frequently Asked Questions
No, a classic Crookes radiometer is powered solely by light (or radiant heat).
A radiometer measures a broad spectrum of radiant energy (including infrared), while a photometer is specifically designed to measure visible light as perceived by the human eye.
In a Crookes radiometer, the motion is primarily due to thermal transpiration (also called thermal creep): gas molecules near the warmer, blackened sides of the vanes receive more momentum, pushing the vane away.
No, it is a low-frequency, specialised term. Most people encounter it only in specific scientific contexts or as a novelty item.