2nd Year Physics Chapter 21 Nuclear Physics Notes MCQs Solutions

physics 12th notes mcqs chapter 21

1. Strong nuclear force acts on:


2. Beta particles posses greater penetration power than that of alpha particles due to its


3. The total energy transferred to a body by means of radiation is measured is units of:


4. The SI unit of radiation dose is:


5. Which of the following will be better shield against gamma rays


6. Positrons are prepared in a process of


7. The substances which slow down the speed of neutron produced during a fission reaction are called:


8. Mass of electron is:                       


9. In fission reaction, heavy water is used as:                   


10. Isobars have the same


11. A solid state detector is basically:                      


12. Absorbed Dose “D” is defined as:


13. A particle having the mass of an electron and having the charge of a proton is called


14. Leptons are particles that do not experience


15. The magnitude of range of radiation particle through matter depends upon:


16. At higher energies more than 02 MeV, the dominant process is:


17. The background radiations that we are exposed per year on the average is


18. Which of the following is similar to electron?


19. Gamma rays are emitted by de-excitation of


20. The process in which a heavy nucleus is broken into two lighter nuclei with the release of energy in called:


21. Thyroid cancer is cured by


22. 1 amu is equal to


23. Gamma rays have penetration power


24. A pair of quark and antiquark makes:


25. When radioactive nucleus emits a ß-particle, the proton- neutron ratio


26. The moderator used in a nuclear reactor will be:         


27. Which of following has no change?


28. Proton was discovered by Rutherford in:          


29. Mass defect per nucleon is called


30. Numbers of isotopes of Neon gas are


31. In sold state detector, the energy needed to produce an electron hole pair is about:


32. Geiger Muller counter is widely used:


33. Which particle has large range in air:


34. Mass of neutron is


35. The number of Quark is


36. Radioactivity happen due to the disintegration of:


37. Specially designed solid state detector can be used to detect


38. The binding energy of deutron is:                       


39. Uranium bomb depends on the process of:


40. Gieger Muller counter always uses


41. The term “dead time” in G.M counter means the time or the order of:


42. The electron was discovered by J.J Thomson by passing an electric discharge through:


43. Geiger counter is a device to detect


44. Charge on an electron was determined by:


45. Wilson cloud chamber is a device used as:


46. The particle which is 7000 times heavier than the electron is called:


47. Which of the following belong are leptons


48. In Wilson Cloud chamber, the ß-particle leave:


49. The building blocks of protons and neutrons are called:


50. The average of the background radiation to which we are exposed:


51. Marie curie and Pierre curie discovered two new radioactive elements which are:


52. Mass of proton is


53. After two half-lives the number of decayed nuclei of an element are


54. When ɣ-rays are emitted, the nuclear mass


55. In Wilson cloud chamber x-particle leave:         


56. When a certain radiation passes through matters it lose energy due to:


57. Materials can be identified by measuring their:


58. The process in which a heavy nucleus is broken into two intermediate nuclei with the release of energy is called


59. In the unit of unified mass scale, The mass of an electron is:


60. The distance at which the radioactive particle comes to rest after emitting from a source is called:


61. The chain reaction is controlled by a series of rods usually made of:


62. Radioactivity was discovered in 1896 by


63. Which of the following statement is correct


64. Charge on neutron is


65. The number of Neutrons in ₉₂U²³⁸ is:


66. Low level radiations effects:                    


67. Tick the correct statement


68. The energy released during fission process is controlled in:


69. Certain radiation detector makes use of the fact that super saturated vapors condense preferentially on ions this type of detector is called:


70. Which of the following are elementary particles?


71. The charge on electron was experimentally determined by Millikan in:


72. The counter which also provide the power to the G.M tube is called:


73. A large amount of energy can be obtained when:


74. Curie is a unit of


75. Thyroid glands play major role in distribution of


76. In solid-state detector, the reverse bias is applied through the two:


77. The binding energy per nucleon is


78. The back ground radiation to which we are exposed on the average per year is


79. The product of the fission reaction of uranium named barium and krypton have a total mass equal to:


80. The mass of β-particle is equal to mass of:


81. The half life of a radio-active element is given by


82. Atomic theory was announced in 1808 by:


83. A mass spectrograph sorts out


84. Which one of the following is not affected by the electric or magnetic field


85. In Wilson Cloud chamber, the ∝-particle leave:


86. The half life of uranium 238 is:    


87. The energy required to breaks up helium nuclear into two protons and two neutron is:


88. The numbers of protons in any atom are always equal to the number of:


89. I amu is equal to:               


90. The half life of I131 is;


91. By passing an electric discharge through a gas at low pressure, the electron was discovered:


92. The nucleus consists of


93. Extremely penetrating particles are:


94. The early Greeks believed that matter waves was: 


95. The energy released by fusion of two deuterons into a helium nucleus is about


96. Fission chain reaction is controlled by


97. In an electronic transition, atom cannot emit:


98. Which of the followings are not hadrons?


99. Three up quarks combine to make a new particle, the charge number on this particle is


100. The number of protons in an atom are always equal to number of


101. The most useful tracer isotope for the treatment of Thyroid gland is:


102. During fission process, a large amount of


103. The particles equal in mass or greater than protons are called


104. The atomic bomb is an example of


105. Which of the following have similar nature as that of electrons:


106. Coloured tv and micro wave oven emits


107. Neutrons and protons in the Nucleus are together called:


108. The charge number of ₅₆B¹⁴¹ is


109. Wilson cloud chamber is an instrument used for


110. The mass and charge of an ∝-particle is:           


111. Both Xenon and cesium have


112. Which nuclear reaction takes place in the sun and stars


113. Neutron was discovered in 1932 by:


114. Nuclear fission reaction can be produced in ₉₂U²³⁸ by:


115. An apparatus used to determine the masses of protons, nuclei, ions and to detect the isotopes is:


116. Cobalt-60 is the source for


117. In liquid metal fast breeder reactors, the type of uranium used is


118. The ratio of the mass of nucleus and the total mass of all the constituents making the nucleus is always:


119. The first atomic reactor was introduced by:                  


120. Dr. Abdus salam unified electromagnetic force and


121. Binding energy for deuteron nucleus is given by


122. Chadwick discovered neutron by the study of scattering of  particulars from


123. The beta particles have_____ path


124. The mass of beta particles is equal to that of


125. Rutherford bombarded a thin sheet of gold with


126. The rate of decay of radioactive substance:      


127. Radio activity was discovered by:                      


128. Beta particle ionizes an atom due to


129. Atoms of an element whose atomic number are the same but have different mass numbers are called:


130. Charge on an electron is


131. Geiger counter was designed by


132. Unified mass scale means that atomic mass is expressed in:


133. Structure of Nucleus successfully explained by:


134. The main source of energy in the stars and the sun is due to:


135. To allow the entry of a or Il-particles, one end of the Geiger counter tube vas a:


136. Neutrons and protons in the nucleus are together called


137. The mass of positron is same as that of


138. The most useful tracer is


139. The mass number of a nucleus is the number of:         


140. When a nucleus emits an ∝-particle, its mass number drops by:


141. The numbers of neutrons in Li are


142. Mass spectrograph is used for identification of:


143. Gamma rays consist of a stream of


144. Nuclei of an element having same charge number but different mass number are called:


145. Cobalt-60 emits gamma rays of energy


146. β-particles are


147. During fusion of hydrogen into helium:


148. The wavelength of -rays is:                      


149. The Isotopes of hydrogen are:


150. The decay constant of a radioactive element depends upon


151. When a nucleus emits an alpha particle, its atomic number decreases by


152. Sub atomic particles are divide into


153. The first artificially produced nuclear transmutation was studied by:


154. The element formed by radioactive decay is called


155. The number of neutrons in the nucleus of ₃Li⁷ are


156. Capture of a neutron by a nucleus results in the formation of


157. The phenomenon of nuclear fission is used in the construction of:


158. The SI unit of decay constant is:


159. One unified mass scale is equal to


160. The time taken for a radioactive element to decay to half of its original number of atoms is called:


161. Artificial radioactivity was discovered by:


162. The isotope 1H1 contains: 


163. Controlled fission chain reaction is maintained in a


164. In G.M, counter, the cylinder is dilled with mixture of gases:


165. Iodine-131 is used for the treatment of


166. The amount of energy required to break the nucleus is called


167. By emitting β- particle and ɣ- Particle simultaneously the nucleus changes its charge by:


168. The activity of radioactive sample:


169. A high potential difference of… is used in G.M counter


170. When nitrogen is bombard by Alpha, particles, then nitrogen nuclei change into


171. The process of nuclear fission was explained by:        


172. When ∝-particle is emitted from any nucleus, its mass number____ and its charge number____


173. The particles equal in mass but greater than proton are


174. Gamma rays from cobalt-60 are used for the treatment of


175. Fluorescence is the property of:


176. The mass of fissionable material needed for self sustaining chain reaction is called:


177. Artificial radio activity is:             


178. The process in which two or more lighter nuclei combine together to form heavier nuclei with release of energy is called:


179. A Curie represents a very strong source of


180. Alpha particles are


181. The reciprocal of decay constant of a radioactive element is


182. The half life of radioactive elements depends upon what among the following:


183. One joule of energy absorbed per kilogram of a body is:


184. Two down and one up quarks make:


185. A naturally occurring disintegration involving the emission of high energy electrons is called:


186. Examples of radiation detector case:


187. In equation I = Io eux , the symbol represents:    


188. Rate of decay is actually described by:


189. Mass of meson is


190. In Wilson cloud chamber, we use


191. For an atom having atomic mass A and atomic number Z, the number of neutrons in the nucleus is:


192. Which one belongs to Lepton’s group?


193. The elements showing radioactivity have atomic number ‘Z’


194. The average amount of energy to remove one nucleon from the nucleus is called:


195. Circulation Blood can be studied by using Radioactive Isotope:


196. When an alpha particle collides with an atom of a gas, it knocks out


197. 1 amu is equal to


198. Gamma rays are


199. The value of 1 u mass =


200. Rutherford determined the size of nucleus to be equal to:


201. Energy emitted when one atom of ₉₂U²³⁵ undergoes fission reaction is:


202. The example of fusion reaction is


203. The interaction of different radiation with matter depends upon:


204. The half life of radium-225 is:


205. Gamma rays are electromagnetic waves like


206. The capture of a neutron by a nucleus results in the formation of:


207. Which of the following have no charge


208. Nuclei of different elements are identified by


Short Questions

1. ₉₂U²³⁸ emits an alpha particle what still be the new element formed?
2. A nuclide ₈₆Rn²²² decays to a new nuclide ‘X’ by two – emission and two β – emission. What is the new nuclide?
3. A particle which produces more ionization is less penetrating. Why?
4. After four half – lives what percent of sample remains?
5. Define decay constant ?
6. Define radioactivity?
7. Describe the principle of operation of a solid state detector of ionizing radiation in terms of generation and detection of change carriers?
8. Discuss the advantages and disadvantages of fusion power from the point of view safety, pollution and resources?
9. Discuss the advantages and disadvantages of nuclear power compared to the use of fossil fuel generated power?
10. Do , β and λ rays comes from the same element? Why do we find all three in many radioactive elements?
11. Electrostatic forces of repulsion between protons, in a nucleus, tend to make the nucleus unstable. Inspite of this the nucleus is stable why is it so ?
12. Explain how a nuclear reactor produces heat as a result of fission?
13. Explain how α – and β – particles may ionize an atom without directly hitting the electrons? What is the difference in the action of the two particles for producing ionization?
14. Find the number of neutrons and protons in ₉₂U²³⁸?
15. For what purpose alcohol or bromine is mixed with principle gas in Geiger tube?
16. Give a brief account of interaction of various types of radiation with matter?
17. Give the mathematical relation for the half life of a radioactive element ?
18. Give the mathematical relation for the half life of a radioactive element ?
19. Give the uses of nuclear radiation on Radiation Therapy?
20. Give two properties of ∝-particles ?
21. Give two properties of neutrons when they interact with the matter?
22. Give two properties of β-particles ?
23. Give two properties of λ-ray ?
24. Give two uses of radio isotopes ?
25. How a radioisotopes be used the determine the effectiveness of a fertilizer?
26. How can radioactive help in the treatment of cancer?
27. How do λ rays differ from X- rays?
28. How does Cl³⁶ differ from Cl³⁷? Why are they considered to be chemically identical even through their nuclei are not the same?
29. How many photons, neutrons and electrons are there in nucleus of ₈₆Rn²²²?
30. How much is a nucleon heavier than electron ?
31. How much mass may be concentrated in the nucleus of atom?
32. How one isotope of an element differs from the other isotope of the same element ?
33. How the isotopes of an element can be separated individually from an element ?
34. How the nucleus of represented ?
35. If a nucleus has half life of one year does this mean that it will completely decay after two years?
36. If you swallowed an α-source and β – source, with would be the more dangerous to you? Explain why?
37. Is it possible that fusion of two small nuciel may accur without collision at extremely high enrgy?
38. It is more difficult to start a fusion reaction than a fission reaction. Why?
39. It is said that nuclear energy is raw heat energy. How heat is produced in a nuclear reactor?
40. Name the element having maximum binding energy?
41. Nuclear energy released under fusion reaction is greater than what is obtained under fission reaction, although release the nuclear energy per fission is 200 Mev as compared to 25 Mev per fusion reaction. Comment?
42. Radium has a half life of 1600 years. How much of 60 gm Radium would be left after 4800 years
43. Shows that 1 amu = 931 Mev?
44. The nucleus of nitrogen contain 9 neutrons. Find its charge number and its number is 16?
45. Water is the batter shield against neutrons than lead? Explain. Why?
46. What are isotopes? What do you they have in common and what are their differences?
47. What are nucleons ?
48. What are radiation detectors?
49. What are stable nuclei ?
50. What are the Atomic Number of He3 and He4?
51. What are the uses of nuclear radiation in medical diagnostics and treatments?
52. What are the uses of Nuclear Reactor?
53. What are transuranic elements ?
54. What do you mean by the term critical mass?
55. What does the name LMFBR stand for?
56. What doo you understand by background radiation? State two sources of this radiation?
57. What factors makes a fusion reaction difficult to achieve?
58. What fraction of a radioactive sample decays after two half lives have elapsed?
59. What information is revealed by the length and shape of the tracks of an incident particle in Wilson cloud chamber?
60. What is a y-decay ?
61. What is a y-ray ?
62. What is an ∝-decay ?
63. What is daughter element ?
64. What is half life of a radioactive element ?
65. What is mass defect?
66. What is meant by mass energy equation ?
67. What is meant by the nuclear exposure? What are the major factors contributing towards nuclear exposure?
68. What is nuclear physics ?
69. What is nucleus ?
70. What is radiation tracer? (b). Describe one application each in medicine agriculture and industry?
71. What is radio isotope ?
72. What is radioactive decay ?
73. What is the basic structure of a solid state detector?
74. What is the mass defect for hydroaen ?
75. What is the mass of a neutron in unified mass scale?
76. What is the principle of a cloud chamber ?
77. What is the principle of Nuclear Reactor?
78. What is the size (diameter) of an atom?
79. What is the size (diameter) of nucleus ?
80. What is the unit of decay constant ?
81. What is β-decay?
82. Which elements are naturally occuring radioactive ?
83. Which of ∝, β and λ – radiation would you advise and why for?(i). Treatment of skin of a patient. (ii). Treatment of flesh just under skin. (iii). Treatment of infection in the interior of the body.
84. Which radiation does would deposit more energy to your body? (a) 10 m Gy to your hand or 1 m Gy does to your entire body?
85. Who discovered a neutron ?
86. Who discovered a positron ?
87. Who discovered a proton ?
88. Who discovered an electron ?
89. Who discovered antiproton ?
90. Who discovered natural radioactivity ?
91. Who found out the charge on an electron ?
92. Who invented cloud chamber ?
93. Why are heavy nuclei unstable?
94. Why must a Geiger Muller tube for detecting ∝– particle have a very thin window? Why does a Geiger Muller tube for detecting λ – rays not need a window at all?
95. Why neutrino releases during a β-decay ?
96. Write an application of tracer technique each in medicine, agriculture and industry?

Long Questions

1. Explain isotopes with the help of examples.
2. Define the terms mass number and atomic number. Also describe the symbolic notation of nuclei elements.
3. Describe mass spectrograph and how it can be used for the detection of isotopes.
4. What is the mass defect and binding energy?
5. What is radioactivity? Discuss emission of
6. What is the phenomenon of nuclear transmutation radio active decay?
7. What is meant by half life of radioactive element? How can it be determined from the decay of radioactive element?
8. Write a notes on the interaction of alpha, beta and gamma rays with matter.
9. Describe the principle, construction and working of Wilson Cloud Chamber.
10. What is G.M counter? Give its construction. How is it used to count the nuclear radiation?
11. What is solid state detector? Also discuss construction and working.
12. What are the nuclear reactions and conditions for the nuclear reactions?
13. Write a detailed note on nuclear fission. What is fission chain reaction? Describe uncontrolled and controlled chain reaction?
14. What is nuclear reactor? Describe the main function of its main parts.
15. Write a detailed note on radiation exposure and its damages.
16. Find the mass defect and the binding energy for tritium, if the atomic mass of tritium is 3.016049.
17. The half life of ₃₈Sr⁹¹ is 9.7 hours. Find its decay constant.
18. The element ₉₁Pa²³⁴ is unstable and decays by beta ray emission with a half life 6.66 hours. State the nuclear reaction and the daughter nuclei.
“19. Find the energy associated with the following reaction:
₇N¹⁴ + ₂He⁴ ——> ₈O¹⁷ + ₁H¹”
“20. Determine the energy associated with the following the following reaction:
₆C¹⁴ ——-> ₇N¹⁴ + ₋₁e⁰”
21. If ₉₂U²³³ decays twice by alpha emission, what is the resulting isotope?
“22. Calculate the energy (in MeV) released in the following fusion reaction:
₁H² + ₁H³ —–> ₂He³ + ₀n¹.”
23. Sheet of lead 5 mm thick reducing the intensity of beam of gamma rays by a factor 0.4. Find the half value thickness of lead sheet which will reduce the intensity to half of its initial value.
24. Radiation from a point source obeys the inverse square law. If the count rate at a distance of 1m from Geiger counter is 360 counts per minute, what will be its count rate at 3m from the source?
25. A 75 kg person receives a whole body radiation dose of 24 m rad, delivered by alpha particles for which RBE factor is 12. Calculate (a) the absorbed energy in joules, and (b) the equivalent dose in rem.

Leave a Reply

Your email address will not be published. Required fields are marked *