At time t = 0 , the activity of a radioactive substance is 1600 Bq. At t= 8 s, the activity remains 100 Bq. The activity at t = 2 s, the is

Step-by-step solution

The activity of a radioactive substance at time t is given by A = A₀ ( 1 2 )^ t T_ 1/2 . Given A₀ = 1600 Bq at t = 0 . At t = 8 s, A = 100 Bq. 100 = 1600 ( 1 2 )^ 8 T_ 1/2 1 16 = ( 1 2 )^ 8 T_ 1/2 ( 1 2 )^4 = ( 1 2 )^ 8 T_ 1/2 8 T_ 1/2 = 4 T_ 1/2 = 2 s. The activity at t = 2 s is: A = 1600 ( 1 2 )^ 2 2 = 1600 1 2 = 800 Bq. Answer: 800 Bq