Explain decay constant and write down its definition.
Explain decay constant and write down its definition.
From the law of radioactive decay,
$\frac{d \mathrm{~N}}{d t}=-\lambda \mathrm{N}$
where $d \mathrm{~N}$ is no. of decayed nuclei in time $d t \mathrm{~N}$ is the no. of remaining nuclei in the time $t \lambda$ is radioactive constant or decay constant.
Writing this equation as follows, $\lambda=-\frac{d \mathrm{~N} / d t}{\mathrm{~N}}$
$\therefore$ The ratio of instantaneous rate of disintegration for a given instant and number of undecay nuclei at that time is called decay constant or radioactive constant.
OR mathematically: The probability of integration per unit time of a radioactive element is called radioactive constant.
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