= Becquerel
{title2=$\mathrm{Bq}=\mathrm{s}^{-1}$}
{wiki}
The <becquerel>, symbol $\mathrm{Bq}$, is the <SI> unit of <radioactive activity>, with $1\,\mathrm{Bq}=1\,\mathrm{s^{-1}}$. An <radioactive activity> of one becquerel means one expected nuclear transformation per second under the stated conditions, not a guarantee of one event in every individual second.
Measured count rate need not equal <radioactive activity>. A <particle detector> registers only some decays because of geometry and <detection efficiency>, and one transformation can emit several particles or none detectable by that instrument. Activity also differs from deposited <energy> or <absorbed dose>: those depend on the emitted particles, their <energies> and where their interactions occur.
Back to article page
