Question:
The half-life of $²15$At is 100 $μ$s. The time taken for the radioactivity of a sample of this nucleus to decay to $\frac116$th of its initial value is
The half-life of $²15$At is 100 $μ$s. The time taken for the radioactivity of a sample of this nucleus to decay to $\frac116$th of its initial value is
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$N = N₀ (1/2)ᵗ/T$ for radioactive decay.
Updated On: Apr 16, 2026
- 6.3 $μ$s
- 40 $μ$s
- 300 $μ$s
- 400 $μ$s
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Verified By Collegedunia
The Correct Option is D
Solution and Explanation
Step 1: $N = N₀ (1/2)ᵗ/T$. For $N/N₀ = 1/16 = (1/2)⁴$, so $t/T = 4$.
Step 2: $t = 4 × 100 = 400$ $μ$s.
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