Half life of a radioactive substance in 30 min . During 2 hrs the fraction of total no of atoms that have decayed would be
Hello Deepika
The initial amount of substance = N(0)
The amount of substance after time (t) = N
Given -
Half time of the substance (T) = 30 minutes
Total time passed (t) = 2 hours
Convert the hours into minutes.
2 hours = 2 × 60 minutes
= 120 minutes.
The fraction for total number of atoms decayed is
N/N(0) = (1/2)^(t/T)
= (1/2)^(120/30)
= (1/2)^(4)
= (1/16)
N = N(0)/16
Thus the fraction of decayed atoms will be 1/16. And the amount remaining will be 1/16 of original amount.