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× 10^17s. If the number of nuclei in the sample is 2.0× 10^21, the activity of the…
NEET UG 2020 — Physics Modern Physics
2020mcqmedium
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:
Official previous-year question
Held on 30 Apr 2020 · Verified 9 Jul 2026.
Options
- A
104Bq
- B
105Bq
- C
106Bq
- D
103Bq
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