2. Solved Papers
  3. JAMIA MILLIA ISLAMIA

JAMIA MILLIA ISLAMIA Jamia Millia Islamia Solved Paper-2014

  • question_answer
    A radioactive substance decays 20% in 10 min If at the start there are \[\frac{20}{27}{{\lambda }_{0}}\] atoms present after what time will the number of atoms be reduced to \[\frac{16}{25}{{\lambda }_{0}}\] atoms?

    A) 5.65 h      

    B) 4.65h     

    C) 3.65 h     

    D) 6.65 h

    Correct Answer: B

    Solution :

                    \[\text{3}.\text{18}\times \text{1}{{0}^{8}}m/s\] \[\text{3}.\text{33}\times {{10}^{\text{8}}}\text{ m}/\text{s}\] Initially there are \[\theta =\text{45}{}^\circ \] atoms which reduces to \[\frac{1}{3}M{{L}^{2}}\] atoms after time t min                                 \[=\frac{2.303}{10}\log \frac{100}{80}=0.223{{\min }^{-1}}\] \[\frac{3}{4}M{{L}^{2}}\]


You need to login to perform this action.
You will be redirected in 3 sec spinner