Q18.In a radioactive material, a fraction of active material remaining after the time t is 9 . The fraction that 16 was remaining after the time t is : 2 (1) 4 (2) 3 5 5 (3) 3 (4) 7 4 8
What This Question Tests
This question assesses the understanding of the exponential decay law in radioactivity and how the fraction of active material remaining changes with time.
Concepts Tested
Formulas Used
N(t)/N0 = e^(-λt)
📚 NCERT Sections This Tests
3.17 — During Nuclear Explosion, One Of The Products Is 90Sr With Half-Life Of
Chemistry Class 11 · Chapter 3
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.
13.4 — Obtain Approximately The Ratio Of The Nuclear Radii Of The Gold Isotope
Physics Class 12 · Chapter 13
13.4 Obtain approximately the ratio of the nuclear radii of the gold isotope 197 79 Au and the silver isotope 10747 Ag .
3.18 — For A First Order Reaction, Show That Time Required For 99% Completion
Chemistry Class 11 · Chapter 3
3.18 For a first order reaction, show that time required for 99% completion is twice the time required for the completion of 90% of reaction.
📋 Question Details
- Chapter
- Nuclei
- Topic
- Radioactive Decay
- Year
- 2020
- Shift
- 03 Sep Shift 1
- Q Number
- Q18
- Type
- MCQ
- NCERT Ref
- Class 12 Physics Ch 13: Nuclei
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