Physics Ontology

One map of physics, three ways in. Drill down on any quantity to see its units, the equations it lives in, and how its values span the universe.

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AA
Quantum

Activity

Rate of radioactive decay; decays per second (becquerel).

SI unit

becquerel (Bq)

Dimension: [ T−1 ][\,T^{-1}\,]

Other units

  • becquerel (Bq)

Order of magnitude

How values of activity span the physical world (in Bq, log scale).

Banana (K-40)
1.50 × 101 Bq
1 g radium
3.70 × 1010 Bq
Lower limit100 BqUpper limit1020 Bq

Appears in 1 equation

Activity
A=λNA = \lambda N

Associated scientists

Ernest Rutherford