NEET · Physics · STD 12 - 13. Nuclei
Given below are two statements : Statement \(I:\) The law of radioactive decay states that the number of nuclei undergoing the decay per unit time is inversely proportional to the total number of nuclei in the sample. Statement \(II:\) The half life of a radionuclide is the sum of the life time of all nuclei, divided by the initial concentration of the nuclei at time \(t =0\). In the light of the above statements, choose the most appropriate answer from the options given below :
- A Both Statement \(I\) and Statement \(II\) are correct
- B Both Statement \(I\) and Statement \(II\) are incorrect
- C Statement \(I\) is correct but Statement \(II\) is incorrect
- D Statement \(I\) is incorrect but Statement \(II\) is correct
Answer & Solution
Correct Answer
(B) Both Statement \(I\) and Statement \(II\) are incorrect
Step-by-step Solution
Detailed explanation
Since, \(dN =-\lambda Ndt\) \(( dN \propto N )\) statement \(I\) is wrong. \(T _{1 / 2}=\) time in which active no. of nuclei becomes half therefore statement \(II\) is wrong.
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