The mean lives of a radioactive substance are `T^(1)` and `T^(2)` for `alpha-`emission and `beta-`emission respectively. If it is decaying by both `beta-`emission and`beta -`emission simultaneously then find its mean life and decay constant ?

Explanation

`:' , lambda = lambda_(1) + lambda _(2)`
`:. , lambda = (1)/( T_(1)) + (1)/(T_(2)) " r " T= (T_(1)T_(2))/( T_(1)+ T_(2))`
` [ :' , T = (1)/(lambda)]`