If ' T ' is the half life of a radioactive substancethen its instantaneous rate of change of activity is proportional to

Step-by-step solution

aligned & Activity, R= -d N d t = N & d R d t = d d t ( N)= d N d t = (- N)=- ^2 N & = _ e 2 T_ 1 / 2 & ^2 N= ( _ e )^2 N ~T _ 1 / 2 ^2 & dR dt 1 ~T _ 1 / 2 ^2 aligned