Recall the formula of activity of a radioactive element in terms of decay constat, R=λN, and we know that the relation between decay constant and half-life is, T=λ0.693⇒R=T0.693×N⇒R=1.4×10170.693×2×1021⇒R=104Bq.
The half life of radioactive sample undergoing α-decay is 1.4×1017s. If the number of nuclei in the sample is 2.0×1021, the activity of the sample is nearly:
Held on 30 Apr 2020 · Verified 9 Jul 2026.
104Bq
105Bq
106Bq
103Bq
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