Q. Half life of a radio active element is 5 min. 10 sec. Time taken for 90% of it to disintegrate is nearly

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Half life of a radio active element is 5 min. 10 sec. Time taken for 90% of it to disintegrate is nearly

Solution:

$t= frac{t_{frac{1}{2}}}{log , 2}$ log $left( frac{N_0}{N} right)$