NEET Sample Paper NEET Sample Test Paper-44

  • question_answer
    The half-life of a radioactive substance is 30 minutes. The tim taken between 40% decay and 85% decay of the same radioactive substance is:

    A) 60                    

    B) 15    

    C) 30                    

    D) 45

    Correct Answer: B

    Solution :

    \[{{\operatorname{R}}_{eff}}={{R}_{wire}}+{{R}_{resistor}}\] \[=10\Omega +990\Omega =1000\Omega \] 'V drop across wire \[{{\operatorname{V}}_{w}}=I\times Rwire\] \[{{\operatorname{V}}_{w}}=\frac{V\,\,battery}{{{\operatorname{R}}_{eff}}}\times 10\Omega \] \[{{\operatorname{V}}_{w}}=\frac{2}{1000}\times 10=2\times {{10}^{-2}}\operatorname{volt}\] \[\frac{\operatorname{V}}{\ell }=0.001\,\operatorname{volt}\]


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