The decay rate of radium at any time `t` is proportional to its mass at that time. Find the time when the mass will be halved of its initial mass.

Explanation

Let the initial amount of radium be `N` and the amount of radium present at any time `t` be `P`.


Given:- `frac{d P}{d t} alpha P`


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`Rightarrow frac{d P}{d t}=-a P`


`Rightarrow frac{d P}{P}=-a d t`


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Integrating both sides, we get


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