 |
| Physics 12th Chapter 17 - Physics of Solids |
Physics 12th Chapter 17 - Physics of Solids Solved MCQs, Important Short Questions and Long Questions Bank
MCQs
Please select the right answer.
1. A solid having regular arrangement of molecules throughout its structure is called
2. A completely filled band is called
3. A conduction band is always:
4. A device used to detect very weak magnetic field produced by brain is named as.
5. A hole in a p-type material is
6. A new class of ceramic materials was discovered in:
7. A pentaralent impurity in Si:
8. A pentavalent impurity is
9. A p-type crystal is
10. A p-type material is formed when a semiconductor is doped with:
11. a p-type semiconductor is obtained by doping germanium or silicon with
12. A semi-conductor in its extremely pure form is called
13. A solid having regular arrangement of molecules throughout its structure is called:
14. A solid in which there is no regular arrangement of molecules is
15. A solid that is intermediate between order and disorder is called:
16. A stress which changes one dimension only is:
17. A stress which decreases the length along one dimension is known as:
18. A substance which has empty conduction band is called
19. A unit cell is the smallest basic structure which is:
20. A vacant or partially filled band is called
21. Above the Curie temperature, Iron is:
22. Acceptor impurities are
23. Amorphous solid are also called:
24. Amorphous solids are:
25. An example of acceptor impurity is:
26. An example of an extrinsic semi conductor is:
27. An example of an intrinsic semi conductor is:
28. An example of donor impurity is:
29. An n-type semiconductor is formed by adding impurity
30. An N-type substance is:
31. An ordinary glass gradually softness into a paste like state before it becomes a very viscous liquid which is possible at:
32. An P-type substance is:
33. Any change produced in shape, volume or length when a body is subjected some external force is called:
34. Artificial polymers are made by a chemical reaction known as:
35. At 0 k semi conductors are
36. Atoms, ions and molecules of crystalline materials maintain their long range order due to:
37. Bulk Modulus is involved when the deformation is:
38. Ceramic materials exhibit super-conductivity at
39. Conduction band may be:
40. Conductors have:
41. Crystalline solid have:
42. Crystalline solids are:
43. Curie temperature for iron is
44. Domains are existed in:
45. Donor impurities are
46. Each atom in a crystalline vibrates about a fixed point with an amplitude that:
47. Example of polymeric solid:
48. Examples of crystalline solids are:
49. Examples of polymeric solids are:
50. For practical purposes, the proportional limit for ductile material is:
51. Force applied on a unit area is called:
52. Hook’s law states that the strain is directly proportional to:
53. If a material sets up a magnetic field which opposes the applied magnetic field it is said to be:
54. If stress increased beyond elastic limit of the material , it becomes permanently changed, this behavior is called
55. In an n-type material, the minority charge carriers are:
56. In n-type substance charge carriers are
57. In n-type substance the minority charge carriers are
58. In p-type substance charge carriers are
59. In p-type substance the majority charge carriers are
60. In p-type substance the minority charge carriers are
61. Insulators are those materials which have
62. Magnetism lags behind the magnetizing current this phenomenon is called
63. Many of the semi-conductors are crystals of the type
64. Materials have specific uses depending upon their characteristics and properties such as:
65. Measure of deformation of body with application of stress is called:
66. Minority carriers in p-type substances are:
67. Modulus of elasticity of material is:
68. Molecules of a solid possess:
69. Narrow forbidden energy gap between the conduction and valence band of a conductor is of the order of
70. Nm⁻² is called
71. N-Type germanium is obtained by doping intrinsic germanium with
72. N-type germanium is obtained by doping intrinsic germanium with
73. On doping, the conductivity of the semi conductor:
74. On introducing a small amount of impurity into a pure semi-conductor, its electrical behaviour:
75. Once the resistance of material drops to zero, the
76. Once the stress is increased than UTS, the material falls into the region of:
77. Ordinary glass becomes a very viscous liquid at:
78. Partially filled conduction and valence bands with a very narrow forbidden energy gap in between them shows the:
79. Polymer solids are:
80. Semi conductor is one which has:
81. SI unit of stress is same as that of
82. Soft magnetic material is
83. Solids with high value of conductivity are called:
84. Substances in which the atoms do not form magnetic dipole are called:
85. Substances which break just after elastic limit is reached, are called
86. Super conductors are used in:
87. The ability of a body to return to its original shape is called
88. The area method for finding strain energy is useful for:
89. The band below the valance band is:
90. The band theory of solids has explained the distinguishing behavior of
91. The conduction band lies:
92. The core of transformer is laminated or reduces.
93. The critical temperature (Te) of lead is
94. The critical temperature for mercury is
95. The critical temperature of Aluminum is:
96. The critical temperature of mercury is
97. The dimension of strain is:
98. The dimension of stress is:
99. The domain theory Of magnet is important to explain the behaviour of:
100. The doped semiconductors are called
101. The electrons occupying by conduction band are:
102. The energy band occupying free electrons is called:
103. The energy band occupying valance electrons is known as:
104. The examples of conductors are:
105. The examples of insulators are:
106. The extension produced in a sample of material depends upon:
107. The field produced by an electron is generated by its
108. The first super conductor was discovered in:
109. The first superconductor was discovered in
110. The force applied on a unit area to produce any change in shape, volume and length is called:
111. The force which maintains the long-range order between atoms of crystalline solid is called:
112. The material whose resistivity becomes zero below a certain temperature:
113. The materials used for semiconductors are
114. The materials whose resistivity becomes zero below a certain temperature are called
115. The maximum stress that a material can withstand is called
116. The maximum stress which a body can bear is:
117. the most suitable metal for making permanent magnet is
118. The number of crystalline systems is
119. The practical use of superconductors is
120. The prosperity of a material to return to its original shape and size on the removal of strain is called:
121. The ratio of applied stress to tensile strain is called:
122. The ratio of applied stress to volumetric strain is called
123. The ratio of stress to strain is called:
124. The ratio of the applied stress to shear strain is called:
125. The ratio of the applied stress to volume strain is called:
126. The resistance of mercury becomes zero at the temperature:
127. The results of mechanical tests are usually expressed in terms of:
128. The S.I. unit of strain is
129. The S.I. unit of stress
130. The S.I. unit of stress is same as that of
131. The smallest three dimensional structure of crystalline solid which repeats over and over again is called
132. The solids are classified as:
133. The strain energy in a deformed wire is actually the gain in the:
134. The substance among the following which breaks after the elastic limit is called:
135. The substances which have partially filled conduction bands are called:
136. The substances with conductivies between 10⁻¹⁰ and 10⁻²⁰ (Ωm)-1 are called
137. The substances with resistivity of the order of 10 ⁴ Ohm-meter
138. The supper conductor was discovered by:
139. The temperature at which the vibrations becomes so great that the structure of the crystal breaks is called:
140. The temperature below which the resistivity of a super conductor falls to zero is called
141. The tensile stress applied is:
142. The theory failed to explain the complete electric behaviour of solid:
143. The transition from solid state to liquid state is actually from:
144. The ultimate tensile strength (UTS) is the:
145. The value of resistivity of semiconductors is of the order of
146. The value of stress beyond which a body is permanently deformed is called
147. The value of stress beyond which the body is permanently deformed will be known as:
148. The whole structure obtained by the repetition of unit cell is called:
149. The word amorphous means:
150. This phenornenon is called:
151. Those materials in which valence and conduction bands are overlap each other are called:
152. To form a P-type semi-conductor, silicon is doped with:
153. To form an N-type semi-conductor, silicon crystal is doped with:
154. To get N-type, the Ge is doped with:
155. Valence band may be:
156. Valence band:
157. What are the substances called which undergo plastic deformation until they break
158. What type of impurity is to be added to the semi conductor material to provide hole:
159. When a battery is connected to a semi-conductor, the current passes through it is due to:
160. When a body is subjected to some external force, deformation is produced in:
161. When a covalent bond is broken in a doped semi conductor:
162. When a Germanium is doped with pentavalent impurity, the doped semi conductor is:
163. When a silicon crystal is doped with a pentavalent element, it becomes
164. When a silicon crystal is doped with a pentavalent impurity, the doped semiconductor is called
165. When stress changes the shape of the object, it is called
166. When the specimen does not recover its original shape after the stress is removed, its behaviour is called:
167. When the stress changes length of a body, it is called:
168. When the stress changes the shape of the body it is called:
169. When the stress changes the volume of the body, it is called:
170. Which of the following are mechanical properties of a material:
171. Which of the following has the least hysteresis loop area
172. Which one is not a ferromagnetic substance?
173. Which one is pentavalent impurity?
174. Which one of the following exhibit good strength to weight ratio
175. Which one of the following has the greatest energy gap
176. Which one of the following is a ductile substance
177. Which one of the following is crystalline solid?
178. Which one of the following is not an acceptor impurity
179. Which one of the following is pentavalent impurity
180. Which one of the following is polymeric solid?
181. Which one pair belongs to accepter impurity?
182. Which type of impurity is to be added to a pure semi-conductor crystal to provide holes:
183. Whole structure of solid obtain by the repetition of unit cells is called:
184. With rise in temperature, the conductivity of semi-conductor material
185. with the rise in temperature, the conductivity of semi-conductor material:
186. Yield stress is another name of:
187. Young's modulus for water is
Short Questions
1. Coercivity of steel is more than iron. Why?
2. Define an elastic limit?
3. Define Bulk modulus?
4. Define coercive current?
5. Define crystal lattice ?
6. Define diamagnetic paramagnetic and ferromagnetic substances. Given their examples?
7. Define elasticity?
8. Define modulus of elasticity show that the units of moduclus of elasticity and stress are the same. b) Also discuss its three kinds?
9. Define modulus of elasticity?
10. Define proportional limit?
11. Define stress and strain. What are their SI units?
12. Define ultimate tensile stress?
13. Define unit cell of crystalline solid?
14. Define yield point ?
15. Define Young’s modulus?
16. Describe the formation of energy bands in solids.
17. Differentiate between brittle and ductile substance?
18. Differentiate between n – type and p- types substances?
19. Differentiate between tensile compressive and shear modes of stress and strain?
20. Discus the mechanism of electrical conduction by holes and electrons in a pure semi – conductor element?
21. Distinguish between a valence band and conduction band?
22. Distinguish between crystalline amorphous and polymetic solids?
23. Distinguish between intrinsic and Extrinsic semi- conductors?
24. Distingusish between indrinsic and extrinsic semi-conductors. How will you get n-type and p-type substances?
25. Draw a stress- strain curve for a ductile material and then define the terms elastic limit yield point and ultimate tensile stress?
26. Energy dissipated per cycle for steel is more as compared to iron. Why?
27. Explain the difference amongst electrical behavior of conductors insulator and semi- conductors in terms of energy band theory?
28. How can the conductivity of a semi-conductor be raised?
29. How strain energy can be determined from the force-extension graph ?
30. How the conductivity of a semiconductor dioc can be raised?
31. Name the energy bands which are necessary for electrical conduction through solids ?
32. Show That the dimensions of stress and pressure are the same?
33. Sugar is dissolved in water easily while oil can not do so. What is the reason?
34. What are brittle substances ?
35. What are conductors ?
36. What are conductors insulators and semi – conductors. Describe each of them?
37. What are ductile substances ?
38. What are elastic constants ?
39. What are insulators ?
40. What are polymeric solid ?
41. What are semiconductors ?
42. What are superconductors?
43. What are valence electrons ?
44. What do you mean by Curie temperature ?
45. What do you mean by hysteresis ?
46. What do you understand by crystal lattice?
47. What do you understand by hysteresis loss?
48. What is a crystalline solid ?
49. What is a curie temperature ?
50. What is a semi-conductor diode ?
51. What is a solid ?
52. What is an amorphous solid ?
53. What is an elastic deformation ?
54. What is bulk modulus ?
55. What is bulk modulus for aluminium ?
56. What is bulk modulus for copper?
57. What is bulk strength ?
58. What is cohesive force?
59. What is compressional stress?
60. What is conduction band ?
61. What is critical temperature?
62. What is domain ?
63. What is doping ?
64. What is energy band theory?
65. What is extrinsic semiconductor ?
66. What is hole ?
67. What is hysteresis cycle ?
68. What is hysteresis loss?
69. What is intrinsic semiconductor ?
70. What is meant by deformation in solid ?
71. What is meant by domain?
72. What is meant by hysteresis loss? How is it used in the construction of a transformer?
73. What is meant by strain energy?
74. What is meant by strain energy? How can it be determined from the force extension graph?
75. What is meant by the word amorphous ?
76. What is n-type substance ?
77. What is plasticity or plastic deformation ?
78. What is p-type substance ?
79. What is semi- conductor diode?
80. What is shear modulus ?
81. What is shear modulus for aliminium ?
82. What is shear modulus for copper?
83. What is shear stress?
84. What is strain ?
85. What is stress?
86. What is superconductor ?
87. What is tensile stress?
88. What is the behaviour of semiconductor diode at zero Kelvin ?
89. What is the curie temperature of iron ?
90. What is the difference between elastic deformation and plastic deformation?
91. What is the nature of gap between a conduction and valence band's of semiconductor ?
92. What is the order or conduction in the semiconductors ?
93. What is the SI unit of modulus of elasticity ?
94. What is the SI unit of stress?
95. What is the source of magnetism of an atom ?
96. What is the stress if the force 'F' is applied on unit area 'A' ?
97. What is the temperature below which mercury can behave as super conductor ?
98. What is the unit of strain ?
99. What is unit cell?
100. What is valence band ?
101. What is young's modulus ?
102. What is young's modulus for aluminium ?
103. What is young's modulus for copper ?
104. What theory successfully explains the conduction through solid ?
105. When first conductor was discovered?
106. Whether atoms, ions or molecules ?
107. Whether every crystalline solid has a definite melting point ?
108. Whether plastic and polythene polymeric solids ?
109. Whether the SI unit of stress is same as that of pressure ?
110. Whether there is a regular arrangement of molecules in crystalline solids ?
111. Who discovered super conductor first?
112. Why crystals do not conduct?
Long Questions
1. Explain the classification of solids.
2. What are the mechanical properties of solids?
3. Explain elastic limit and yield strength with the help of graph.
4. What is meant by strain energy? Derive the relation for strain energy in deformed material from the area under the force extensions graph?
5. What are the electrical properties of solids?
6. Explain conductors, insulators and semi-conductors on the basis of energy band theory.
7. What is doping? Describe the formation of n-type and p-type semi-conductors.
8. Explain electrical conduction by electrons and holes in semi-conductors.
9. What are the superconductors?
10. Describe magnetic properties of solids. Describe the types of magnets.
11. What is energy band theory?
12. Explain Hysteresis loop.
13. A 25 cm diameter cylinder is subjected to a load of 2500 kg. Calculate the stress on the bar in mega pascals?
14. A 0 m long wire is subjected to stretching force and its length increases by 20 cm, Calculate the tensile strain and the percent elongation which the wire undergoes?
15. A wire 2.5 m long and cross section are 10⁻⁵ m² is stretched 5 mm by a force of 100 N in the elastic region. Calculate. (i) Strain (ii) Young’s Modulus (iii) The energy stored in wire = U =?
16. What stress would cause a wire to increase in length by 0.01 % if the Young’s Modulus of the wire is 12 x 10¹⁰ Pa. What force would produce this stress if the diameter of wire is 0.56 mm?
17. The length of a steel wire is 0 m and its cross sectional area is 0.03 x 10⁻⁴ m². Calculate the work done in stretching the wire where force of 100 N is applied with in the elastic region. Young’s Modulus of steel is 3 x 10¹¹ Nm⁻².
18. A cylindrical copper wire and a cylindrical steel wire each of length 1.5 and diameter 2.0 mm are joined one end to form a composite wire of 3.0 m long. The wire is loaded until its length becomes 3.003 m. Calculate the strain in copper and steel wire and the force applied to the wire. (Young’s Modules of Copper is 2 x 10¹¹ Pa and for steel is 2.0 x 10¹¹ Pa).