Welcome to your Nuclei MCQs Mock Test of Class 12th Physics
1.
Q.1. Samples of two radioactive nuclides A and B are taken λA and λB are the disintegration constants of A and B respectively. In which of the following cases, the two samples can simultaneously have the same decay rate at any time?
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Q 2. Radioactivity is the phenomenon associated with
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Q 3. Which of the following are not emitted by radioactive substances?
5.
Q.5. For a nuclear fusion process, suitable nuclei are
6.
Q.6. In the uranium radioactive series, the initial nucleus is 92U238 and that the final nucleus is 82Pb206. When uranium nucleus decays to lead, the number of α particles and β particles emitted are
7.
Q.7. The nuclear radius is of the order of
8.
Q.8. Particles which can be added to the nucleus of an atom without changing its chemical properties are called
9.
Q.9. The radius of a nucleus is
10.
Q.10. Nucleus of an atom whose atomic mass is 24 consists of
11.
Q.11. The electrons cannot exist inside the nucleus because
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Q.12. In …X… water is circulated though the reactor vessel and transfers energy to steam generator in the …Y… Here, X and Y refer to
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Q.13. A nuclei having same number of neutron but different number of protons / atomic number are called
14.
Q.14. Which one of the following has the identical property for isotopes?
15.
Q.15. The number of protons in an atom of atomic number Z and mass number A is
16.
Q.16. When the number of nucleons in nuclei increases, the binding energy per nucleon
17.
Q.17. Mp denotes the mass of a proton and Mn that of a neutron. A given nucleus, of binding energy B, contains Z protons and N neutrons. The mass M(N, Z) of the nucleus is given by (c is the velocity of light)
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Q.18. Mass energy equation was propounded by
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Q.19. The mass of an atomic nucleus is less than the sum of the masses of its constituents. This mass defect is converted into
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Q.20. Which of the following statement is not true regarding Einsteins mass energy relation?
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Q.21. The curve of binding energy per nucleon as a function of atomic mass number has a sharp peak for helium nucleus. This implies that helium
22.
Q.22. Nuclear forces are
23.
Q.23. Nuclear forces exists between
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Q.24. The antiparticle of electron is
25.
Q.25. Neutron decay in free space is given as follows 0n1 → 1H1 + -1e0 + [] Then the parenthesis [ ] represents a
26.
Q.26. Radioactivity is
27.
Q.27. γ-rays are deflected by
28.
Q.28. Beta rays emitted by a radioactive material are
29.
Q.29. Which of the following is not a mode of radioactive decay ?
30.
Q.30. The half-life period and the mean life period of a radioactive element are denoted respectively by Th and Tm. Then
31.
Q.31. In γ ray emission from a nucleus
32.
Q.32. Artificial radioactivity was discovered by
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Q.33. Radioactive samples are stored in lead boxes because it is
34.
Q.34. The process of radioactive radiations remains unaffected due to
35.
Q.35. A radioactive material undergoes decay by ejecting electrons. The electron ejected in this process is
36.
Q.36. The same radioactive nucleus may emit
37.
Q.37. Which of the following of a radioactive material is a measure of its instability?
38.
Q.38. The rate of disintegration at a given instant, is directly proportional to the number of Nuclei present at that instant. This is the statement of
39.
Q.39. Three specimens A, B, C of same radioactive element has activities 1 microcurie, 1 rutherford and 1 becquerel respectively. Which specimen has maximum mass?
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Q.40. If a radioactive element is placed in an evacuated chamber, then the rate of radioactive decay will
41.
Q 41. Tritium is an isotope of hydrogen whose nucleus Triton contains 2 neutrons and 1 proton. Free neutrons decay into p + e¯+v¯. If one of the neutrons in Triton decays, it would transform into He3 nucleus. This does not happen. This is because [NCERT Exemplar]
42.
Q.42. Radioactive substance emits
44.
Q43. When a β-particle is emitted from a nucleus then its neutron-proton ratio
45.
Q44.. A radioactive nucleus emits a beta particle. The parent and daughter nuclei are
46.
Q45. The quantity which is not conserved in a nuclear reaction is
47.
Q.46. The ‘rad’ is the correct unit used to report the measurement of
48.
Q.47. One curie is equal to
49.
Q.48. Half life of radioactive element depends upon
50.
Q.49. A nuclear reaction is given by ZXA → Z+1YA + -1e0 + ν̅
51.
Q.50. Fusion reaction occurs at temperatures of the order of
