Q18.The half life period of a radioactive substance is 60 days. The time taken for 7 th of its original mass to 8 disintegrate will be : (1) 120 days (2) 130 days (3) 180 days (4) 20 days
What This Question Tests
This question requires calculating the number of half-lives needed for a given fraction of a radioactive substance to disintegrate and then determining the total time elapsed.
Concepts Tested
Formulas Used
N = N0 (1/2)^n
n = t / T_half
📚 NCERT Sections This Tests
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📋 Question Details
- Chapter
- Nuclei
- Topic
- Radioactive Decay and Half-Life
- Year
- 2022
- Shift
- 28 Jul Shift 1
- Q Number
- Q18
- Type
- MCQ
- NCERT Ref
- Class 12 Physics Ch 13: Nuclei
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