NEET Physics Nuclei Questions Solved


The half-life of a radioactive material is 3h. If the initial amount is 300g, then after 18h, it will remain

(a) 4.68 g                                     (b) 46.8 g

(c) 9.375 g                                   (d) 93.75 g

(a) Number of half-lives

        n=tT1/2=183=6                  T1/2 = half life period

Amount remained after n half-lives

       N=N012n                           N0=initial countN=final count

Given,   N0=300g

          N=300126=300×164=4.68 g

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