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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: - A galvanometer coil has a resistance of 15 ohm and gives full scale deflection
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Topics: Radioactivity
(83)
Subject: Physics
(2479)
Important MCQs Based on Medical Entrance Examinations To Improve Your NEET Score
- A galvanometer coil has a resistance of 15 ohm and gives full scale deflection
- A bucket full of water is revolved in a vertical circle of 2m
- Equal charge q each are placed at the vertices AQ and B of an equilateral triangle
- As a light wave travels from one medium to another which of its following properties
- Two spherical conductors A and B of radii 1 mm and 2 mm are separated by a distance
Topics: Radioactivity (83)
Subject: Physics (2479)
Important MCQs Based on Medical Entrance Examinations To Improve Your NEET Score
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