Question -
Answer -
Half-life of the radioactiveisotope = T years
Original amount of theradioactive isotope = N0
(a) Afterdecay, the amount of the radioactive isotope = N
It is given that only 3.125%of N0 remains after decay. Hence, we can write:
Where,
λ = Decay constant
t =Time
Hence, the isotope will takeabout 5T years to reduce to 3.125% of its original value.
(b) Afterdecay, the amount of the radioactive isotope = N
It is given that only 1% of N0 remainsafter decay. Hence, we can write:
Since, λ =0.693/T
Hence, the isotope will takeabout 6.645T years to reduce to 1% of its original value.