Db
Học thuậtThân thiện
Definition
- Noun:
- A logarithmic unit of sound intensity: A unit used to measure the intensity of sound, calculated as ten times the logarithm of the ratio of a sound's intensity to a reference intensity.
- A transuranic element: A chemical element with an atomic number higher than that of uranium, typically radioactive and artificially produced.
Usage Examples
- As a unit of sound intensity:
- The noise level in the factory was measured at 85 db.
- A whisper is about 30 db, while a jet engine can be over 140 db.
- As a chemical element:
- Scientists synthesized a new isotope of the element db in the laboratory.
- Db is part of the actinide series on the periodic table.
Advanced Usage
- "db level": Refers specifically to a measurement of sound pressure level.
- The concert's db level exceeded the city's noise ordinance limits.
- In technical contexts: Often used with prefixes like "dBm" (decibels relative to one milliwatt) in electronics or "dB(A)" (A-weighted decibels) in acoustics to specify the measurement scale.
- The signal strength was -70 dBm.
Variants and Related Words
- Decibel (dB): The full term for the unit of sound measurement. 'db' is a common abbreviation.
- The decibel scale is logarithmic, not linear.
- Dubnium (Db): The systematic name for the chemical element with atomic number 105.
- Dubnium-268 is one of the most stable isotopes of Db.
Synonyms
- For the unit: Decibel (dB).
- For the element: Dubnium (the formal IUPAC name).
Important Notes
- Capitalization: When referring to the chemical element, it is conventionally written with a capital 'D' (Db) as an element symbol. When referring to the sound unit, it is typically written in lowercase (db), though 'dB' is the more standard form.
- Context is Crucial: The meaning is entirely dependent on context (scientific/technical vs. acoustical/engineering).
Noun
- a logarithmic unit of sound intensity; 10 times the logarithm of the ratio of the sound intensity to some reference intensity
- a transuranic element