Q24.Half-lives of two radioactive elements A and B are 20 minutes and 40 minutes, respectively. Initially, the samples have an equal number of nuclei. After 80 minutes, the ratio of decayed numbers of A and B nuclei will be: (1) 1 : 4 (2) 5 : 4 (3) 1 : 16 (4) 4 : 1
What This Question Tests
This question involves calculating the number of decayed nuclei for two different radioactive elements after a certain time, using their respective half-lives and initial equal number of nuclei.
Concepts Tested
Formulas Used
N = N₀ (1/2)^(t/T_½)
N_decayed = N₀ - N
📚 NCERT Sections This Tests
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 .
3.17 — 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.
13.5 — The Q Value Of A Nuclear Reaction A + B ® C + D Is Defined By
Physics Class 12 · Chapter 13
13.5 The Q value of a nuclear reaction A + b ® C + d is defined by Q = [ mA + mb – mC – md]c2 where the masses refer to the respective nuclei. Determine from the given data the Q-value of the following reactions and state whether the reactions are exothermic or endothermic. (i) 11 H+13 H →12 H+12 H (ii) 126 C+126 C →1020 Ne+ 24 He Atomic masses are given to be m ( 12 H ) = 2.014102 u m ( 13 H) = 3.016049 u m ( 126 C ) = 12.000000 u m ( 1020 Ne ) = 19.992439 u
📋 Question Details
- Chapter
- Nuclei
- Topic
- Radioactivity, Half-life
- Year
- 2016
- Shift
- 03 Apr
- Q Number
- Q24
- Type
- MCQ
- NCERT Ref
- Class 12 Physics Ch 13: Nuclei
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