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A radioactive substance has a half-life of four months. Three-fourth of substance will decay in
Options
(a) 3 months
(b) 4 months
(c) 8 months
(d) 12 months
Correct Answer:
8 months
Explanation:
Substance left undecayed N = N₀ – (3 / 4) N₀ = (1 /4) N₀
N / N₀ = (1 / 2)ⁿ
where n = number of half lives
.·. 1 / 4 = (1 / 2)ⁿ (or), n = 2 n = t / T₁/₂ t = nT₁/₂ = 2 × 4 = 8 months.
Related Questions: - In Moseley’s law √ν=a(z-b), the values of the screening constant for K-series
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- Perfectly black body radiates the energy 18 J/s at 300K. Another ordinary body of e=0.8
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Topics: Radioactivity
(83)
Subject: Physics
(2479)
Important MCQs Based on Medical Entrance Examinations To Improve Your NEET Score
- In Moseley’s law √ν=a(z-b), the values of the screening constant for K-series
- The nuclei of which one of the following pairs of nuclei are isotones?
- Perfectly black body radiates the energy 18 J/s at 300K. Another ordinary body of e=0.8
- In Young’s double slit experiment, the ratio of maximum and minimum intensities
- A boat taken 2h to travel 8km and back in still water.If the velocity of water 4 km/h
Topics: Radioactivity (83)
Subject: Physics (2479)
Important MCQs Based on Medical Entrance Examinations To Improve Your NEET Score
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