Q28.The half life of a radioactive substance is 5 years. After x years a given sample of the radioactive substance gets reduced to 6. 25% of its initial value. The value of x is ____
What This Question Tests
This question directly tests the understanding of radioactive decay and half-life, requiring calculation of the number of half-lives passed for a given reduction in substance.
Concepts Tested
Formulas Used
N = N₀(1/2)^(t/T)
Fraction remaining = (1/2)^n
📚 NCERT Sections This Tests
3.17 — During Nuclear Explosion, One Of The Products Is 90Sr With Half-Life Of
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3.17 During nuclear explosion, one of the products is 90Sr with half-life of 28.1 years. If 1mg of 90Sr was absorbed in the bones of a newly born baby instead of calcium, how much of it will remain after 10 years and 60 years if it is not lost metabolically.
11.3 — The Photoelectric Cut-Off Voltage In A Certain Experiment Is 1.5 V.
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11.3 The photoelectric cut-off voltage in a certain experiment is 1.5 V. What is the maximum kinetic energy of photoelectrons emitted?
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3.25 Sucrose decomposes in acid solution into glucose and fructose according to the first order rate law, with t1/2 = 3.00 hours. What fraction of sample of sucrose remains after 8 hours ?
📋 Question Details
- Chapter
- Nuclei
- Topic
- Radioactivity and Half-life
- Year
- 2022
- Shift
- 29 Jun Shift 2
- Q Number
- Q28
- Type
- Numerical
- NCERT Ref
- Class 12 Physics Ch 13: Nuclei
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