# 225+ Electrostatics Objective Questions and Answers

## Electrostatics Objective Questions

The below list provides all the multiple-choice questions related to electrostatics.

Answers are available at the bottom of the article.

1. Which is the most superior dielectric out of the following?

2. Which of the following statements associated with capacitors is wrong?

3. Two capacitors each having capacitance C and break down voltage V are joined in series. The capacitance and break down voltage of the combination is

4. A capacitance of 1 μF equals

5. Dielectric constant for mica is nearly

6. The units of capacitance are

7. Which of the following expression is correct for electric field strength?

8. A condenser suitable for D.C. only is

9. Dielectric strength____ with increasing thickness

10. The force between two charges is 120 N. If the distance between the charges is doubled, the force will be

11. Which of the following capacitors will have the least variation?

12. The capacitance of a capacitor is not affected by

13. Paper condenser is

14. In a concentric cable capacitor the diameters of the inner and outer cylinders are 3 and 10 mm respectively. If εr for insulation is 3, find its capacitance per meter.

15. Inside a charge hollow conducting sphere, the potential will be

16. A positive and a negative charge are initially 50 mm apart. When they are moved close together so that they are now only 10 mm apart, the force between them will be

17. A capacitance is a circuit component that opposes the change in circuit

18. The charge on an isolated conductor resides

19. In a capacitive circuit

20. The unit of dielectric strength is given by

21. A unit tube of flux is known as____ tube

22. The total deficiency or excess of electrons in a body is known as

23. The presence of an uncharged conductor near a charged one increases the

24. Out of the following capacitors of identical rating which one will have the smallest dimensions?

25. What is the value of capacitance that must be connected in parallel with 50 pF condenser to make an equivalent capacitance of 150 pF?

26. A mica capacitor and a ceramic capacitor both have the same physical dimensions. Which will have more value of capacitance?

27. The units of volume charge density are

28. In a multilayer dielectric material on either side of a boundary.

29. An ideal voltage source will charge an ideal capacitor

30. A variable capacitance is one whose capacitance

31. Which of the following statements is correct?

32. Tangential component of the electric field on a perfect conductor will be

33. In the case of a lossy capacitor, its series equivalent resistance value will be

34. A capacitor of 80 μF is charged to a potential difference (p.d.) of 250V. The charge acquired by it is

35. The potential inside a charged hollow sphere is

36. An, electrolytic capacitor is generally made to provide

37. The value of one Farad in e.s.u. will be

38. One volt is the same as

39. Electric flux in coulombs emanating from any surface of a cube containing C coulombs of charge at its center is

40. Dielectric strength of the medium

41. Capacity of a parallel plate condenser can be increased by

42. ____ capacitors can be used only for D.C.

43. The unit of capacitance is

44. If a current of 2 A passes through a lamp for 200 seconds, the number of coulombs of charge passing through the lamp in that time will be

45. The relation between the breakdown voltage V and the thickness (t) of the dielectric is given by V =At2/3​​, where A is a constant depending on the nature of the medium and also on the thickness t. The above statement is known as

46. Two plates of a parallel plate capacitor after being charged from a constant voltage source are separated apart by means of insulated handles, then the

47. The relation between electric polarization and susceptibility indicates that electric polarization is

48. If a third equal and similar charge is placed between two equal and similar charges, then this third charge will

49. The line of force due to charged particles are

50. The unit of electric intensity is

51. Electric intensity at any point in an electric field is equal to the____ at that point.

52. In the case of a lossy capacitor, its series equivalent resistance value will be

53. If three 15 μF capacitors are connected in series, the net capacitance is

54. A field line and an equipotential surface are

55. Which of the following capacitors has a relatively shorter shelf life?

56. Which of the following capacitor is preferred in the case of single-phase motor?

57. Which one of the following statements does not state that the electrostatic field is conservative?

58. Three capacitors each of breakdown voltage 500 V are connected in parallel. The breakdown rating of the combination will be

59. For closer tolerances which of the following capacitors is usually preferred?

60. Which capacitor will be physically smaller for the same ratings?

61. A large sphere P of radius R is charged positively. It is momentarily connected to a small sphere Q of radius r. The two spheres now have the same

62. The capacity of a spherical conductor is 1 picofarad then its diameter would be

63. Dielectric strength of a material depends on

64. A parallel plate capacitor has a capacitance of 10 μF. If the linear dimensions of the plates are doubled and the separation between them has also doubled the value of the capacitor would be

65. Electric potential at the center of a charged conductor is

66. A capacitor having a capacitance of 5 μF is charged to a potential difference of 10,000 V. The energy stored in the capacitor is

67. ____capacitors are used in transistor circuits.

68. What will happen to an insulating medium if voltage more than the breakdown voltage is applied to it?

69. The ratio of electric flux density to electric field intensity is called____ of the medium

70. The property of a capacitor to store electricity is called its

71. A capacitor having capacitance of 40 μF is connected across 250 V D.C. source. The charging current will be least

72. Which of the following statements is correct?

73. The electric field at a point situated at distance cl from the straight charged conductor is

74. The time constant and R-C circuit may also be defined as the time during which the charging current falls to____ percent of its initial maximum value.

75. The power dissipated in a pure capacitor is

76. Three capacitors each of the capacity C are given. The resultant capacity 2/3 C can be obtained by using them

77. Dielectric strength of mica is

78. When a dielectric slab is introduced in a parallel plate capacitor, the potential difference between plates will

79. The dielectric constant (relative permittivity) of glass is given by

80. A dielectric material must be

81. Check the correct relation

82. It was suggested by ____that the electric field should be imagined to be divided into tubes of force containing a fixed number of lines of force.

83. Permittivity is expressed in

84. Which of the following statement(s) is/are valid in the case of conductors in electrostatic fields?

85. Dielectric strength of a material depends on

86. If AC voltage is applied to a capacitive circuit, the alternating current can flow in the circuit because

87. Internal heating of a capacitor is usually attributed to

88. The condensers of 20 μF and 40 μF capacitance are connected in series across a 90 V supply.

After charging, they are removed from the supply and are connected in parallel with positive terminals connected together and similarly the negative terminals.

Then the voltage across them will be

89. When a dielectric is placed in an electric field the field strength

90. The electric field between the two spheres of a charged spherical condenser

91. ____at a point is equal to the negative potential gradient at that point.

92. Which of the following material has the least value of dielectric constant?

93. The electric field intensity at a point situated at a distanced from a straight charged conductor is proportional to

94. “The total electric flux through any closed surface surrounding charges is equal to the amount of charge enclosed”. The above statement is associated with

95. A medium behaves like dielectric when the

96. Air capacitors are generally available in the range

97. When the dielectric is homogeneous, the potential gradient is

98. Inside a hollow conducting sphere

99. The capacitor preferred for high-frequency circuits is

100. Putting the plates of a charged capacitor apart

101. The capacitor preferred for high-frequency circuits is

102. The dielectric strength of a medium is usually expressed in

103. The voltage applied across a ceramic dielectric produces an electrolytic field 100 times greater than air. What will be the value of the dielectric constant?

104. Which of the following capacitors are preferred for high-frequency circuits?

105. A paper capacitor is usually available in the form of

106. An electric dipole is placed in an electric field generated by a point charge

107. The direction of the lines of force at any point is the direction along which a unit ____charge placed at that point would move if free to do so

108. The voltage applied across a dielectric produces an electrostatic field 50 times greater than air. The dielectric constant of the dielectric will be

109. If an ohmmeter reading immediately goes practically to zero and stays there while checking a capacitor, the capacitor is

110. The potential difference across a capacitor of capacitance 20 μF is increased uniformly from 0 to 240 V in 1 second. The charging current will be

111. Energy density in a static electric field is given by

112. The point charges Q and 2Q are placed at a distance R apart. Where should a third point charge be placed, So that it is in equilibrium

113. Which of the following medium will have the highest value of relative permittivity?

114. If an ohmmeter reading immediately goes practically to zero and stays there, the capacitor is

115. A glass slab is put within the plates of a charged parallel plate condenser. Which of the following quantities does not change?

116. The dissipation factor of good dielectric is of the order of

117. “The surface integral of the normal component of the electric displacement D over any closed surface equals the charge enclosed by the surface”. The above statement is associated with

118. The electric potential due to an electric dipole of length l at a point distance r away from it will be doubled if the

119. The bridge used for the measurement of the value of the capacitance is

120. ___ at a point may be defined as equal to the lines of force passing normally through a unit crosssection at that point.

121. When 4 volts e.m.f is applied across a 1 farad capacitor, it will store the energy of

122. The equipotential line due to point charge Q is

123. Two capacitors each having capacitance C and breakdown voltage V are joined in series. The capacitance and breakdown voltage of the combination will be

124. The capacitance G is charged through a resistance R. The time constant of the charging circuit is given by

125. If the sheet of bakelite is inserted between the plates of an air capacitor, the capacitance will

126. A variable capacitor of 100 μF carries a charge of 0.35 μC. The capacitance is subsequently reduced to 40 pF. The voltage appearing across the capacitor after reduction of its capacitance will be

127. For which of the following parameter variation, the capacitance of the capacitor remains unaffected?

128. In a capacitor, the electric charge is stored in

129. Two spheres of radii r1 and r2 are connected by a conducting wire. Each of the spheres has been given a charge Q. Now

130. Electric field intensity is a____ quantity

131. If the dielectric of a capacitor is replaced by a conducting material the

132. Which of the following capacitors will have the least value of breakdown voltage?

133. In a cable capacitor, voltage gradient is maximum at the surface of the

134. Paper capacitors usually have tolerance of

135. A capacitor charged to 200 V has 2000 μC of charge. The value of capacitance will be

136. The dissipation factor of a good dielectric is of the order of

137. During the dielectric breakdown of a capacitor

138. 1 volt/metre is same as

139. Which medium has the least dielectric strength?

140. A potential of 400 V is applied to a capacitor, the plates of which are 4 mm apart. The strength of the electric field is

141. Fields are said to be circularly polarized if their magnitudes are

142. A soap bubble is given a negative charge then its radius

143. The area of plates of the parallel plate capacitor, to obtain a capacity of 0.3 x​ ​10-3 μF if they are separated by a distance of 10mm and a dielectric between them of permittivity = 2.5, will be

144. The ohmmeter reading for a short-circuited capacitor is

145. The capacitance of a capacitor is influenced by

146. The capacity of the capacitor bank used in power factor correction is expressed in terms of

147. The direction of electric field due to positive charge is

148. Electric displacement is a____quantity

149. The potential gradient at which the dielectric of the condenser just gets punctured is called

150. The energy of a charged capacitor resides in

151. The absolute permittivity of free, space is given by

152. The ability of charged bodies to exert force on one another is attributed to the existence of

153. Coulomb’s law for the force between electric charges most closely resembles with

154. Electric field intensity between plates of a parallel plate condenser is E. Now if a dielectric of medium of dielectric constant ϵ is introduced between the plates, the electric field intensity will become

155. In order to remove static electricity from machinery

156. Electric intensity (E) at any point in an electric field is equal to

157. The inverse of capacitance is called

158. To prevent the generation of static charges on rubber or flat leather

159. Two conductors having the same type of charges are connected by a conducting wire. There would not be any change in the amount of charges on them if

160. Which of the following statements is incorrect?

161. The electric field inside a perfectly conducting media is

162. In a charge-free space, Poisson’s equation results in which one of the following?

163. Across the surface of a charged conductor, the electric

164. The ratio of the charge stored by two metallic spheres raised to the same potential is 6. The ratio of the surface areas of the sphere is

165. Which of the following capacitors will have the least energy stored in it?

166. The electrostatic force between two charges of one coulomb each and placed at a distance of 0.5 m will be

167. The capacitance between two plates increases with

168. In a cable capacitor, voltage gradient is maximum at the surface of the

169. A capacitor stores 0.24 coulombs at 10 volts. Its capacitance is

170. In a parallel plate capacitor, a dielectric slab is introduced. Then the

171. The relative permittivity has the following units

172. “The force of attraction or repulsion between two charges Q1 and Q2 at a distanced meters apart is proportional to the product of charges and inversely proportional to the square of the distance between the two charges”. The above statement is associated with

173. Two metal plates distance ‘d’ apart form a capacitor of value C farads. Another metal plate of thickness d/2 and of the same area is inserted in between these two plates, the capacitance of this three plate capacitor will be

174. ___capacitors are mainly used for radio-frequency tuning

175. Two electrons moving parallel to each other at the same velocity will

176. A ceramic and a mica capacitor have the same physical dimensions. Which has the higher value of capacitance?

177. A capacitor consists of

178. ___capacitors are used for audio frequency and radio frequency coupling and tuning

179. The electric field intensity at a point situated 4 meters from a point charge is 200 N/C. If the distance is reduced to 2 meters. the field intensity will be

180. While checking a good 0.05 μF capacitor by ohmmeter, it’s reading will

181. If the dielectric of a capacitor is replaced by a conducting material

182. Mica capacitors are characterized by all of the following except

183. While testing a capacitor with ohm meter, if the capacitor shows charging, but the final resistance reading is appreciably less than normal, it can be concluded that the capacitor is

184. The sparking between two electrical contacts can be reduced by inserting a

185. Which of the following statement is true?

186. The relation between the breakdown voltage V and the thickness t of the dielectric is given as V =​​ At2/3 where A is a constant which depends on the nature and thickness of the medium. This statement is known as

187. The breakdown voltage for paper capacitors is usually

188. A conducting body has a surface charge density of a coulombs/m2, the field intensity at its surface will be

189. Energy stored in the electric field of a capacitor C when charged from a D.C source of voltage V is equal to____ joules

190. The capacitor charged up to 5 ms, as per the current profile given in the figure, is connected across an inductor of 0.6 mH. Then the value of voltage across the capacitor after 1 μs will approximately be

191. ___ is that property of a capacitor which delays any change of voltage across it

192. For preventing the generation of static charge on rubber or flat leather

193. Electric field inside a hollow metallic charged sphere is

194. Which of the following statements is incorrect?

195. When the plate area of a parallel plate capacitor is increased keeping the capacitor voltage constant, the force between the plates

196. Which of the following capacitors is marked for polarity?

197. The unit of polarization is the same as that of

198. The time constant of an R-C circuit is defined as the time during which capacitor charging voltage actually rises to____ percent of____ its value.

199. Which one of the following statements is correct? On a conducting surface boundary, electric field lines are

200. The number of Faraday tubes of flux passing through a surface in an electric field is called

201. ___ field is associated with the capacitor.

202. A positively charged glass rod attracts an object. The object must be

203. Which of the following materials has the highest value of dielectric constant?

204. An equipotential surface is one which has all points at____ potential

205. The electric potential due to an electric dipole at an axial point distant r from the dipole is related to r as

206. The electric potential at the surface of an atomic nucleus (z = 50) of radius 9 x​​ 10-15 m is

207. The phenomenon of an uncharged body getting charged merely by the nearness of a charged body is known as____

208. Which of the following is not a vector?

209. “The surface integral of the normal component of the electric intensity E over a closed surface is equal to 1/Ε0 ​​times the total charge inside it”. The above statement is known as

210. For making a capacitor, it is better to select a dielectric having

211. If three 10 μF capacitors are connected in parallel, the net capacitance is

212. The potential gradient across the material of low permittivity is____ than across the material of high permittivity.

213. Dielectric strength of a medium

214. A charge which when placed in a vacuum from an equal and similar charge repels with a force of 9 x 103N​​, is known as

215. Polarization of dielectric materials results in

216. A single core cable used of 33000 V has a conductor diameter 10 mm and an internal diameter of the sheath of 25 mm. The maximum electrostatic stress in the cable is

217. The mass of an electron is equal to

218. lf C be the capacitance, V be the potential difference and I is the current, then 1/CV will have the unit of

219. A capacitor in a circuit became hot and ultimately exploded due to wrong connections, which type of capacitor it could be?

220. A charge q is divided into two parts q1, and (q – q1) what is the ratio q/q1 so that the force between the two parts placed a given distance apart is maximum

221. An uncharged conductor is placed near a charged conductor, then

222. In a capacitor, the electric charge is stored in

223. While testing a capacitor with ohmmeter, if the capacitor shows charging but the final resistance reading is appreciably less than normal the capacitor is

224. Capacitance increases with

225. The value of dielectric constant for vacuum is taken as

226. A hollow sphere of charge does not produce an electric field at any

227. Which of the following capacitors can be used for temperature compensation ?

228. The value of E within the field due to a point charge can be found with the help of

229. When a capacitor undergoes a dielectric breakdown

230. As per Coulomb’s law

231. If three capacitors C1, C2 and C3 of values of 1 μF, 2 μF, and 4 μF respectively are in series and connected across a potential of 230V, then charge on each capacitor is

232. If a 6 iF capacitor is charged to 200 V, the charge in coulombs will be

233. An electrolytic capacitor can be used for

234. A gang condenser is a

235. With steady D.C. voltage from a battery applied to a capacitance, after it charges to the battery voltage, the current in the circuit

236. The relative permittivity of free space is given by

237. For removing static charge from machinery the

238. Equal charges are given to two spheres of different radii. The potential will

239. A region around a stationary electric charge lias

240. A capacitor consists of two

241. For a good 0.05 μF capacitor ohmmeter reading should

242. Two copper spheres A (hollow) and B (solid) are of same diameter and are charged to the same potential.