Q19.If f denotes the ratio of the number of nuclei decayed (Nd) to the number of nuclei at t = 0, (N0) then for a collection of radioactive nuclei, the rate of change of f with respect to time is given as: [λ is the radioactive decay constant] (1) −λ(1 −e−λt) (2) λ(1 −e−λt) (3) λe−λt (4) −λe−λt
What This Question Tests
The question asks for the rate of change of the fraction of decayed nuclei, requiring the application of the radioactive decay law and its derivative with respect to time.
Concepts Tested
Formulas Used
N(t) = N_0 e^(-λt)
N_d(t) = N_0 - N(t)
📚 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 .
13.2 — Obtain The Binding Energy Of The Nuclei 5626Fe And 20983 Bi In Units Of
Physics Class 12 · Chapter 13
13.2 Obtain the binding energy of the nuclei 5626Fe and 20983 Bi in units of MeV from the following data: m ( 5626Fe ) = 55.934939 u m ( 20983 Bi ) = 208.980388 u
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
- Radioactive decay
- Year
- 2021
- Shift
- 27 Jul Shift 1
- Q Number
- Q19
- Type
- MCQ
- NCERT Ref
- Class 12 Physics Ch 13: Nuclei
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