Answer:
N = 500Bq
Explanation:
No = 2000Bq
Time (T) = 10years
T½ = 5 years.
N = ?
T½ = In2 / λ
T½ = 0.693 / λ
λ = 0.693 / t½
λ = 0.693 / 5
λ = 0.1386
The ratio between the two activities is
(N / No) = e⁻^λt
N = No * e⁻^λt
N = 2000 * e^⁻⁰.¹³⁸⁶ * ¹⁰
N = 2000 * e⁻¹.³⁸⁶
N = 2000 * 0.25
N = 500Bq
The activity of Co-60 after 10 years would be 500Bq
