activity

Physical quantity in nuclear physics, measured in becquerel, revealing the average number of nucleuses experiencing a spontaneous reaction per second

EntityQ317949

Also known as radioactive activity · activity referred to a radionuclide · activity of a radionuclide · radioactivity

Subclass of: rate
, physical quantity
, reciprocal duration

Overview

From Wikipedia, the free encyclopedia · Read full article · Text CC BY-SA 4.0

Specific activity is the activity per unit mass of a radionuclide and is a physical property of that radionuclide. It is usually given in units of becquerel per kilogram (Bq/kg), but another commonly used unit of specific activity is the curie per gram (Ci/g). 1 Ci/g = 37 TBq/kg.

Overview

All data

27 statements · 15% with external sources · numbers in brackets are citations

Quantity symbol (LaTeX): A
2
Sources
1.Stated in ISO 80000-10:2019 Quantities and units — Part 10: Atomic and nuclear physics
2.Stated in International Electrotechnical Vocabulary
View statement on Wikidata ↗
ISQ dimension: \mathsf{T}^{-1}
Recommended unit of measurement: becquerel
2
Sources
1.Stated in SI Brochure (9th edition): Concise summary
2.Stated in ISO 80000-10:2019 Quantities and units — Part 10: Atomic and nuclear physics
View statement on Wikidata ↗
reciprocal second
1
Sources
1.Stated in ISO 80000-10:2019 Quantities and units — Part 10: Atomic and nuclear physics
View statement on Wikidata ↗
Defining formula: A = -\frac{\mathrm{d} N}{\mathrm{d} t}
1
Sources
1.Stated in ISO 80000-10:2019 Quantities and units — Part 10: Atomic and nuclear physics
View statement on Wikidata ↗
In defining formula: A symbol represents: activity
N symbol represents: number of nuclei
t symbol represents: duration
Different from: activity
radioactivity
active electronic component

On other databases

12 identifiers linking activity across the web's reference databases

Data quality

statements

15%

externally sourced

Source last edited July 22, 2026. AIDB refreshes this page daily.

Suggest a fact or correction

Links

Use this data

curl https://aidb.si/api/v1/entities/Q317949

API docs, limits & keys

Cite this page

AIDB. (2026). activity (Q317949). Retrieved from https://aidb.si/e/activity-Q317949