12th Class Physics Electric Charges and Fields Question Bank

done MCQ - Electric Charges and Fields Total Questions - 147

• question_answer1)
  Electricity produced on rubbing is:
  A)
  static electricity done clear
  B)
  electromagnetic done clear
  C)
  current electricity done clear
  D)
  None of these done clear
  View Solution play_arrow

• question_answer2)
  When a person combs his hair, static electricity is sometimes generated by what process?
  A)
  Contact between the comb and hair results in a charge done clear
  B)
  Friction between the comb and hair results in the transfer of electrons done clear
  C)
  Conduction between the comb and hair done clear
  D)
  Induction between the comb and hair done clear
  View Solution play_arrow

• question_answer3)
  During the process of rubbing of two bodies, which charged particle transfer during the process:
  A)
  Electron                         done clear
  B)
  Proton   done clear
  C)
  Neutron                         done clear
  D)
  Positron done clear
  View Solution play_arrow

• question_answer4)
  The quantity whose unit is kilo ampere hour:
  A)
  current done clear
  B)
  potential difference done clear
  C)
  power               done clear
  D)
  charge done clear
  View Solution play_arrow

• question_answer5)
  A body is positively charged, it implies that:
  A)
  there is only positive charge in the body done clear
  B)
  there is positive as well as negative charge in the body but the positive charge is more than negative charge done clear
  C)
  there is equal positive and negative charge in the body but the positive charge lies in the outer regions done clear
  D)
  negative charge is displaced from its position done clear
  View Solution play_arrow

• question_answer6)
  A body can be negatively charged:
  A)
  by adding some electrons to it done clear
  B)
  by adding some protons to it done clear
  C)
  by removing some electrons from it done clear
  D)
  by removing some protons from it done clear
  View Solution play_arrow

• question_answer7)
  There are two types of electric charge-positive charges and negative charges. The property which differentiates the two types of charges is:
  A)
  field of charge        done clear
  B)
  amount of charge done clear
  C)
  strength of charge   done clear
  D)
  polarity of charge done clear
  View Solution play_arrow

• question_answer8)
  Object may acquire an excess or deficiency of charge by:
  A)
  hammering          done clear
  B)
  heating done clear
  C)
  shaking                          done clear
  D)
  rubbing done clear
  View Solution play_arrow

• question_answer9)
  What will happen when we rub a glass rod with silk cloth?
  A)
  Some of the electrons from the glass rod are transferred to the silk cloth done clear
  B)
  The glass rod gets positive charge and silk cloth gets negative charge done clear
  C)
  New charges are created in the process of rubbing done clear
  D)
  Both a and b are correct done clear
  View Solution play_arrow

• question_answer10)
  When two bodies are rubbed against each other, they acquire:
  A)
  equal and similar charges done clear
  B)
  equal and opposite charges done clear
  C)
  unequal and similar charges done clear
  D)
  unequal and opposite charges done clear
  View Solution play_arrow

• question_answer11)
  Charge is the property associated with matter due to which it produces and experiences:
  A)
  electric effects only done clear
  B)
  magnetic effects only done clear
  C)
  both electric and magnetic effects done clear
  D)
  None of the above done clear
  View Solution play_arrow

• question_answer12)
  In general, metallic ropes are suspended on the carriers taking inflammable materials. The reason is:
  A)
  to control the speed of the carrier done clear
  B)
  to keep the centre of gravity of the carrier nearer to the earth done clear
  C)
  to keep the body of the carrier in contact with the earth done clear
  D)
  None of the above done clear
  View Solution play_arrow

• question_answer13)
  When \[{{10}^{19}}\]electrons are removed from a neutral plate, the electric charge on it is:
  A)
  -1.6C                done clear
  B)
  +1.6C   done clear
  C)
  \[{{10}^{19}}C\]                     done clear
  D)
  \[{{10}^{-19}}C\] done clear
  View Solution play_arrow

• question_answer14)
  When some charge is transferred to 'A', it readily gets distributed over the entire surface of 'A'. If some charge is put on 'B', it stays at the same place. Here, A and B refer to:
  A)
  insulator, conductor done clear
  B)
  conductor, insulator done clear
  C)
  insulator, insulator   done clear
  D)
  conductor, conductor               done clear
  View Solution play_arrow

• question_answer15)
  Which of the following is responsible for the conduction of electricity in solids?
  A)
  Free electrons     done clear
  B)
  Anion and Cation   done clear
  C)
  Electron-hole pair   done clear
  D)
  Ionised particles done clear
  View Solution play_arrow

• question_answer16)
  What is responsible for the conduction of electricity in Liquids?
  A)
  Free electrons    done clear
  B)
  Anion and Cation done clear
  C)
  Electron-hole pair done clear
  D)
  Ionised particles done clear
  View Solution play_arrow

• question_answer17)
  Which of the following materials is the best conductor of electricity?
  A)
  Platinum                        done clear
  B)
  Gold     done clear
  C)
  Silicon                           done clear
  D)
  Copper done clear
  View Solution play_arrow

• question_answer18)
  Which of the following is not an insulator?
  A)
  Dry air              done clear
  B)
  Diamond done clear
  C)
  Ebonite             done clear
  D)
  Human body done clear
  View Solution play_arrow

• question_answer19)
  The dielectric constant of an insulator cannot be:       
  A)
  3.5 done clear
  B)
  2 done clear
  C)
  4.2                         done clear
  D)
  \[\infty \] done clear
  View Solution play_arrow

• question_answer20)
  Which of the following phenomenon is responsible for attracting bits of paper with a help of charged comb:
  A)
  Electrostatic shielding done clear
  B)
  Electrostatic induction    done clear
  C)
  Electrostatic potential done clear
  D)
  Electric field    done clear
  View Solution play_arrow

• question_answer21)
  A method of charging a conductor without bringing a charged body in contact with it is called:
  A)
  magnetization done clear
  B)
  electrification done clear
  C)
  electrostatic induction done clear
  D)
  electromagnetic induction done clear
  View Solution play_arrow

• question_answer22)
  When a body is charged try induction, then the body:
  A)
  becomes neutral done clear
  B)
  loses whole of the charge on it done clear
  C)
  does not lose any charge done clear
  D)
  loses part of the charge on it done clear
  View Solution play_arrow

• question_answer23)
  A cylindrical conductor is placed near another positively charged conductor. The net charge acquired by the cylindrical conductor will be:
  A)
  positive only done clear
  B)
  negative only done clear
  C)
  zero done clear
  D)
  either positive or negative done clear
  View Solution play_arrow

• question_answer24)
  A conducting sphere is negatively charged. Which of the following statements is true?
  A)
  The charge is uniformly distributed throughout the entire volume done clear
  B)
  The charge is located at the center of the sphere done clear
  C)
  The charge is located at the bottom of the sphere because of gravity done clear
  D)
  The charge is uniformly distributed on the surface of the sphere done clear
  View Solution play_arrow

• question_answer25)
  What would happen, if 2 identical bodies of opposite charge come in contact?
  A)
  Charge is exchanged done clear
  B)
  Charge is neutralized done clear
  C)
  Positive and negative charge is induced in both bodies done clear
  D)
  Depends on the duration of contact done clear
  View Solution play_arrow

• question_answer26)
  Which of the following is not a property of electric charge?
  A)
  Additivity of charge done clear
  B)
  Quantisation of charge done clear
  C)
  Conservation of charge done clear
  D)
  Superposition of charge done clear
  View Solution play_arrow

• question_answer27)
  Which of the following has the same charge as the basic unit of charge?
  A)
  Electron done clear
  B)
  Proton done clear
  C)
  Positron done clear
  D)
  Both a and b done clear
  View Solution play_arrow

• question_answer28)
  Charge on a body is integral multiple of i.e., It implies the law of:
  A)
  Conversation of charge done clear
  B)
  Conversation of mass done clear
  C)
  Conversation of energy done clear
  D)
  Quantisation of charge done clear
  View Solution play_arrow

• question_answer29)
  A polythene piece rubbed with wool is found to have a negative charge of \[6\times {{10}^{-7}}C\]. The number of electrons transferred to polythene from wool is:
  A)
  \[3.75\times {{10}^{10}}\] done clear
  B)
  \[9.6\times {{10}^{10}}\] done clear
  C)
  \[9.6\times {{10}^{12}}\] done clear
  D)
  \[3.75\times {{10}^{12}}\] done clear
  View Solution play_arrow

• question_answer30)
  If \[{{10}^{9}}\] electrons move out of a body to another body every second, then the time required to get a total charge of 1 C on the other body is:
  A)
  250 years done clear
  B)
  100 years done clear
  C)
  198 years done clear
  D)
  150 years done clear
  View Solution play_arrow

• question_answer31)
  The number of electrons that must be removed from an electrically neutral silver dollar to give it a charge of +2.4 C is:
  A)
  \[2.5\times {{10}^{9}}\] done clear
  B)
  \[1.5\times {{10}^{19}}\] done clear
  C)
  \[1.5\times {{10}^{19}}\] done clear
  D)
  \[2.5\times {{10}^{-19}}\] done clear
  View Solution play_arrow

• question_answer32)
  If a charge on the body is 1 nC, then how many electrons are present on the body?    
  A)
  \[1.6\times {{10}^{19}}\] done clear
  B)
  \[6.25\times {{10}^{9}}\] done clear
  C)
  \[6.25\times {{10}^{9}}\] done clear
  D)
  \[6.25\times {{10}^{28}}\] done clear
  View Solution play_arrow

• question_answer33)
  An object of mass 1 kg contains \[4\times {{10}^{20}}\] atoms. If one electron is removed from every atom of the solid, the charge gained by the solid in 1 g is:
  A)
  \[2.8\,C\] done clear
  B)
  \[6.4\times {{10}^{-2}}C\] done clear
  C)
  \[3.6\times {{10}^{-3}}C\] done clear
  D)
  \[9.2\times {{10}^{-4}}C\] done clear
  View Solution play_arrow

• question_answer34)
  Coulomb's law relates two charges and distance between them describing the electric force as being:
  A)
  proportional to the sum of the charges done clear
  B)
  inversely proportional to the distance between charges done clear
  C)
  proportional to the product of the charges and inversely proportional to the distance done clear
  D)
  proportional to the product of the charges and inversely proportional to the square of distance done clear
  View Solution play_arrow

• question_answer35)
  Which of the following statements is true about electric forces?
  A)
  Electric forces are produced by electric charges done clear
  B)
  Like charges attract, unlike charges repel done clear
  C)
  Electric forces are weaker than gravitational forces done clear
  D)
  Positive and negative charges can combine to produce a third type of charge done clear
  View Solution play_arrow

• question_answer36)
  In case of Coulomb's law, which quantity has to be measured accurately so that force due to the charges is more accurate:
  A)
  Magnitude of one of the charge done clear
  B)
  Distance between charges done clear
  C)
  Permittivity done clear
  D)
  None of the above done clear
  View Solution play_arrow

• question_answer37)
  What is the SI unit of permittivity of free space:
  A)
  Wb done clear
  B)
  F done clear
  C)
  \[{{C}^{2}}{{N}^{-1}}{{m}^{-2}}\] done clear
  D)
  \[{{C}^{2}}{{N}^{1}}{{m}^{2}}\] done clear
  View Solution play_arrow

• question_answer38)
  The constant k in Coulomb's law depends on;
  A)
  nature of medium done clear
  B)
  system of units done clear
  C)
  intensity of charge done clear
  D)
  Both a and b done clear
  View Solution play_arrow

• question_answer39)

  In figure, two positive charges, \[{{q}_{2}}\] and \[{{q}_{3}}\] fixed along the Y-axis, exert a net electric force in the +x direction on a charge \[{{q}_{1}}\] fixed along the X-axis. If a positive charge Q is added at (x, 0), the force on \[{{q}_{1}}\]:       `                                                                   (NCERT EXEMPLAR)

   
  A)
  shall increase along the positive X-axis done clear
  B)
  shall decrease along the positive X-axis done clear
  C)
  shall point along the negative X-axis done clear
  D)
  shall increase but the direction changes because of the intersection of Q with \[{{q}_{2}}\] and \[{{q}_{3}}\] done clear
  View Solution play_arrow

• question_answer40)
  Which of the following statement is not a similarity between electrostatic and gravitational forces?
  A)
  Both the forces obey inverse square law done clear
  B)
  Both the forces operate over very large distances done clear
  C)
  Both the forces are conservative in nature done clear
  D)
  Both the forces are always attractive in nature done clear
  View Solution play_arrow

• question_answer41)
  The force between two small charged sphere having charges of \[1\times {{10}^{-7}}\,C\] and \[2\times {{10}^{-7}}\,C\] placed 20 cm apart in air is:
  A)
  \[4.5\times {{10}^{-2}}\,N\] done clear
  B)
  \[4.5\times {{10}^{-3}}N\] done clear
  C)
  \[5.4\times {{10}^{-2}}N\]                    done clear
  D)
  \[5.4\times {{10}^{-3}}N\] done clear
  View Solution play_arrow

• question_answer42)
  The nucleus of helium atom contains two protons that are separated by a distance \[3.0\text{ }\times \text{ }10-15m\]. The magnitude of the electrostatic force that each proton exerts on the other is:
  A)
  20.6N               done clear
  B)
  25.6N   done clear
  C)
  15.6N                            done clear
  D)
  12.6N done clear
  View Solution play_arrow

• question_answer43)
  Two insulated charged metallic spheres P and Q have their centres separated by a distance of 60 cm. The radii of P and Q are negligible compared to the distance of separation. The mutual force of electrostatic repulsion, if the charge on each is \[3.2\text{ }\times \text{ }{{10}^{-7}}\text{ }C\] is:
  A)
  \[5.2\times {{10}^{-4}}\,N\] done clear
  B)
  \[2.5\times {{10}^{-3}}N\] done clear
  C)
  \[1.5\times {{10}^{-3}}\,N\]                  done clear
  D)
  \[3.5\times {{10}^{-4}}N\] done clear
  View Solution play_arrow

• question_answer44)
  Two point charges of \[+3\mu C\] and \[+4\mu C\] repel each other with a force of 10 N. If each is given an additional charge of \[6\mu C\] the new force is:
  A)
  2N done clear
  B)
  4N done clear
  C)
  5N done clear
  D)
  7.5N  done clear
  View Solution play_arrow

• question_answer45)
  The ratio of magnitude of electrostatic force and gravitational force for an electron and a proton is:
  A)
  \[6.6\times {{10}^{39}}\] done clear
  B)
  \[2.4\times {{10}^{39}}\] done clear
  C)
  \[6.6\times {{10}^{29}}\] done clear
  D)
  \[2.4\times {{10}^{29}}\] done clear
  View Solution play_arrow

• question_answer46)
  The electrostatic attracting force on a small sphere of charge \[0.2\,\mu C\] due to another small sphere of charge \[-0.4\,\mu C\] in air is 0.4 N. The distance between the two sphere is:
  A)
  \[43.2\times {{10}^{-6}}m\] done clear
  B)
  \[42.4\times {{10}^{-3}}m\] done clear
  C)
  \[18.1\times {{10}^{-3}}m\]      done clear
  D)
  \[19.2\times {{10}^{-6}}m\] done clear
  View Solution play_arrow

• question_answer47)
  An electron enters uniform electric field maintained by parallel plates and of value \[E\,V{{m}^{-1}}\] with a velocity \[m{{s}^{-1}}\], the plates are separated by a distance d metre, then acceleration of the electron in the field is:
  A)
  \[\frac{Ee}{m}\]                         done clear
  B)
  \[\frac{-Ee}{m}\] done clear
  C)
   \[\frac{Ee}{md}\]                                  done clear
  D)
  \[Ee=\frac{d}{m}\] done clear
  View Solution play_arrow

• question_answer48)
  Under the action of a given coulombic force the acceleration of an electron is \[2.5\times {{10}^{22}}\,m{{s}^{-2}}\]. Then the magnitude of the acceleration a proton under the action of same force is nearly:
  A)
  \[1.6\times {{10}^{-19}}m{{s}^{2}}\] done clear
  B)
  \[9.1\times {{10}^{31}}m{{s}^{-2}}\] done clear
  C)
  \[1.5\times {{10}^{19}}m{{s}^{-2}}\] done clear
  D)
  \[1.6\times {{10}^{27}}m{{s}^{-2}}\] done clear
  View Solution play_arrow

• question_answer49)
  The acceleration for electron and proton due to electrical force of their mutual attraction when they are \[1\,\overset{{}^\circ }{\mathop{A}}\,\]apart is:
  A)
  \[3.1\times {{10}^{22}}m{{s}^{-2}},\,1.3\times {{10}^{19}}m{{s}^{-2}}\] done clear
  B)
  \[3.3\times {{10}^{18}}m{{s}^{-2}},\,3.2\,\times {{10}^{16}}m{{s}^{-2}}\] done clear
  C)
  \[2.5\times {{10}^{22}}\,m{{s}^{-2}},\,1.4\times {{10}^{19}}m{{s}^{-2}}\] done clear
  D)
  \[2.5\times {{10}^{18}}m{{s}^{-2}},\,1.3\times {{10}^{16}}m{{s}^{-2}}\] done clear
  View Solution play_arrow

• question_answer50)
  In superposition principle, the force acting on the given charge by other charges is:
  A)
  proportional to the given number charges             done clear
  B)
  inversely proportional to the given number charges done clear
  C)
  unaffected by other charges done clear
  D)
  None of the above   done clear
  View Solution play_arrow

• question_answer51)
  Each of the two points charges are doubled and their distance is halved. Force of interaction becomes n times, where n is:
  A)
  4                      done clear
  B)
  1         done clear
  C)
  1/16                              done clear
  D)
  16 done clear
  View Solution play_arrow

• question_answer52)
  A charge 'q' is placed at the centre of the line joining of two equal +ve charge 'Q. The system of the three charges will be in equilibrium, if q=
  A)
  \[-\frac{Q}{2}\]              done clear
  B)
  \[-\frac{Q}{4}\] done clear
  C)
  \[\frac{Q}{4}\]                           done clear
  D)
  \[\frac{Q}{2}\] done clear
  View Solution play_arrow

• question_answer53)
  Two spheres having charges +Q and -Q is kept at a certain distance from each other. A force F acts between the two spheres. If a third sphere with charge Q is kept between then it experiences a force in magnitude and direction as:
  A)
  8 F towards +Q charge done clear
  B)
  8 F towards -Q charge done clear
  C)
  Zero having no direction done clear
  D)
  4 F towards +Q charge done clear
  View Solution play_arrow

• question_answer54)

  Two charges q and \[-3q\] are fixed on X-axis separated by distanced. Where should a third charge 2q be placed from A such that it will not experience any force?

   
  A)
  \[\frac{d-\sqrt{3}d}{2}\]             done clear
  B)
  \[\frac{d+\sqrt{3}d}{2}\] done clear
  C)
  \[\frac{d+3d}{2}\]                     done clear
  D)
  \[\frac{d-3d}{2}\] done clear
  View Solution play_arrow

• question_answer55)
  Three point charges are placed on the following points along the X-axis: \[4\mu C\] at x = 0, \[3\mu C\] at x = 20 cm; and \[-5\mu C\] at x = 40 cm. What is the value of force on -3u€ (approximately):
  A)
  6N       done clear
  B)
  4N      done clear
  C)
  3N                               done clear
  D)
  5N done clear
  View Solution play_arrow

• question_answer56)
  Consider the charge q, q and -q placed at the vertices of an equilateral triangle of each side L. The sum of forces acting on each charge is:
  A)
  \[\frac{{{q}^{2}}}{4\sqrt{2}\pi {{\varepsilon }_{0}}{{l}^{2}}}\]                      done clear
  B)
  \[\frac{-{{q}^{2}}}{4\pi {{\varepsilon }_{0}}{{l}^{2}}}\] done clear
  C)
  \[\frac{{{q}^{2}}}{4\pi {{\varepsilon }_{0}}{{l}^{2}}}\]                     done clear
  D)
  zero done clear
  View Solution play_arrow

• question_answer57)
  Three charges of equal magnitude q are placed at the vertices of an equilateral triangle of side l. The force on a charge Q placed at the centroid of the triangle is:
  A)
  \[\frac{3Qq}{4\pi {{\varepsilon }_{0}}{{l}^{2}}}\]                    done clear
  B)
  \[\frac{2Qq}{4\pi {{\varepsilon }_{0}}{{l}^{2}}}\] done clear
  C)
  \[\frac{Qq}{2\pi {{\varepsilon }_{0}}{{l}^{2}}}\]                      done clear
  D)
  zero done clear
  View Solution play_arrow

• question_answer58)

  Four point charges are placed at the corners of a square ABCD of side 10 cm, as shown in figure. The force on a charge of \[1\mu C\] placed at the centre of square is:

   
  A)
  7N        done clear
  B)
  8N done clear
  C)
  2N                               done clear
  D)
  zero done clear
  View Solution play_arrow

• question_answer59)
  V/m is the SI unit of which physical quantity:
  A)
  Electric potential   done clear
  B)
  Electric field done clear
  C)
  Electrostatic force    done clear
  D)
  Electric dipole moment done clear
  View Solution play_arrow

• question_answer60)
  The electric field at a point is:
  A)
  always continuous done clear
  B)
  continuous, if there is no charge at that point done clear
  C)
  discontinuous, if there is a charge at that point done clear
  D)
  Both (b) and (c) are correct done clear
  View Solution play_arrow

• question_answer61)
  The dimensional formula of electric field intensity is:
  A)
  \[\left[ {{M}^{-1}}{{L}^{1}}{{T}^{3}}{{A}^{-1}} \right]\] done clear
  B)
  \[\left[ M{{L}^{-1}}{{T}^{-3}}{{A}^{1}} \right]\] done clear
  C)
  \[\left[ {{M}^{1}}{{L}^{1}}{{T}^{-3}}{{A}^{-1}} \right]\] done clear
  D)
  \[\left[ {{M}^{1}}{{L}^{2}}{{T}^{1}}{{A}^{1}} \right]\] done clear
  View Solution play_arrow

• question_answer62)
  If the charge on an object is doubled, then electric field becomes:                       
  A)
  half done clear
  B)
  double done clear
  C)
  unchanged done clear
  D)
  thrice done clear
  View Solution play_arrow

• question_answer63)
  A charged particle is free to move in an electric field. It will travel:
  A)
  always along a line of force done clear
  B)
  along a line of force, if its initial velocity is zero           done clear
  C)
  along a line of force, if it has same initial velocity in the direction of an active angle with the line of force done clear
  D)
  None of the above       done clear
  View Solution play_arrow

• question_answer64)
  Which of the charge will have an electric field directed radially outwards from the charge at any point in space?
  A)
  Positive charge     done clear
  B)
  Negative charge    done clear
  C)
  Dipole               done clear
  D)
  System of charges   done clear
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• question_answer65)
  A force of 2.25 N acts on a charge of \[15\times {{10}^{-4}}C.\] The intensity of electric field at that point is:
  A)
  \[150\,N{{C}^{-1}}\]                done clear
  B)
  \[15\,N{{C}^{-1}}\] done clear
  C)
  \[1500\,N{{C}^{-1}}\]              done clear
  D)
  \[1.5\,N{{C}^{-1}}\] done clear
  View Solution play_arrow

• question_answer66)
  A particle of mass \[{{10}^{-3}}kg\] and charge \[5\mu C\] is thrown at a speed of \[20\,m{{s}^{-1}}\] against a uniform electric field of strength\[2\times {{10}^{5}}\,N{{C}^{-1}}\]. The distance travelled by particle before coming to rest is:  
  A)
  0.1 m                            done clear
  B)
  0.2 m    done clear
  C)
  0.3 m                            done clear
  D)
  0.4 m done clear
  View Solution play_arrow

• question_answer67)
  An electron initially at rest falls a distance of \[1.5\,cm\] in a uniform electric field of magnitude \[2\times {{10}^{4}}N/C\]. The time taken by the electron to fall this distance is:
  A)
  \[1.3\times {{10}^{2}}s\]                      done clear
  B)
  \[2.1\times {{10}^{-12}}s\] done clear
  C)
  \[1.6\times {{10}^{-10}}s\]                   done clear
  D)
  \[2.9\times {{10}^{-9}}\,s\] done clear
  View Solution play_arrow

• question_answer68)
  The electric field that can balance a charged particle of mass \[3.2\times {{10}^{-27}}\,kg\] is (Given that the charge on the particle is \[1.6\times {{10}^{-19}}C\])
  A)
  \[19.6\times {{10}^{-8}}N{{C}^{-1}}\] done clear
  B)
  \[20\times {{10}^{-6}}N{{C}^{-1}}\] done clear
  C)
  \[19.6\times {{10}^{8}}N{{C}^{-1}}\] done clear
  D)
  \[20\times {{10}^{6}}N{{C}^{-1}}\] done clear
  View Solution play_arrow

• question_answer69)
  Deuteron and a-particle in air are at separation \[1\,\overset{{}^\circ }{\mathop{A}}\,\].The magnitude of electric field intensity on \[\alpha \]-particle due to deuteron is:
  A)
  \[5.6\times {{10}^{11}}N/C\]          done clear
  B)
  \[1.44\text{ }\times {{10}^{11}}\text{ }N/C\] done clear
  C)
  \[2.828\text{ }\times {{10}^{11}}\text{ }N/C\]       done clear
  D)
  zero done clear
  View Solution play_arrow

• question_answer70)
  Electric field required to keep a water drop of mass 'm' just to remain suspended when charged with 1 electron is:
  A)
  \[mg\]                            done clear
  B)
  \[\frac{mg}{e}\] done clear
  C)
  emg                              done clear
  D)
  \[\frac{em}{g}\] done clear
  View Solution play_arrow

• question_answer71)

  Directions (Q. Nos. 71-73): Refer to the given figure and answer the following questions.

  Five equal charges each of value g are placed at the corners of a regular pentagon of side a. The electric field at the centre of the pentagon is:

   
  A)
  \[\frac{q}{4\pi {{\varepsilon }_{0}}{{r}^{2}}}\] done clear
  B)
  \[\frac{{{q}^{2}}}{4\pi {{\varepsilon }_{0}}{{r}^{2}}}\] done clear
  C)
  \[\frac{2q}{4\pi {{\varepsilon }_{0}}{{r}^{2}}}\]                       done clear
  D)
  zero done clear
  View Solution play_arrow

• question_answer72)
  What will be the electric field at centre O, if the charge from one of the corners (say A) is removed?
  A)
  \[\frac{q}{4\pi {{\varepsilon }_{0}}{{r}^{2}}}\] along OA done clear
  B)
  \[\frac{2q}{4\pi {{\varepsilon }_{0}}{{r}^{2}}}\] along OA done clear
  C)
  \[\frac{{{q}^{2}}}{4\pi {{\varepsilon }_{0}}{{r}^{2}}}\]along OA done clear
  D)
  \[\frac{2q}{4\pi {{\varepsilon }_{0}}{{r}^{2}}}\] along OA done clear
  View Solution play_arrow

• question_answer73)
  What will be the electric field at O, if the charge 9 at A is replaced by-q?
  A)
  \[\frac{q}{4\pi {{\varepsilon }_{0}}{{r}^{2}}}\] along OB done clear
  B)
  \[\frac{2q}{4\pi {{\varepsilon }_{0}}{{r}^{2}}}\]along OA done clear
  C)
  \[\frac{4q}{4\pi {{\varepsilon }_{0}}{{r}^{2}}}\]along OC done clear
  D)
  zero done clear
  View Solution play_arrow

• question_answer74)
  The tracks of three charged particles in a uniform electrostatic field are shown in the figure. Which particle has the highest charge to mass ratio?
  A)
  A                      done clear
  B)
  B        done clear
  C)
  C                                  done clear
  D)
  A and B done clear
  View Solution play_arrow

• question_answer75)
  Electric field lines provide information about:
  A)
  field strength                   done clear
  B)
  direction done clear
  C)
  nature of charge      done clear
  D)
  All of these done clear
  View Solution play_arrow

• question_answer76)
  Which of the following is true about electric field lines:
  A)
  They start from positive charge and end at negative charge done clear
  B)
  Two field lines do not cross each other done clear
  C)
  They do not form closed loops done clear
  D)
  All of the above done clear
  View Solution play_arrow

• question_answer77)
  Electric field lines contract length wise, it shows:
  A)
  repulsion between same charges done clear
  B)
  attraction between opposite charges done clear
  C)
  no relation between force and contraction done clear
  D)
  electric field lines do not move on straight path done clear
  View Solution play_arrow

• question_answer78)
  Which of the following figures represents the electric field lines due to a single positive charge?
  A)
    done clear
  B)
  done clear
  C)
  done clear
  D)
    done clear
  View Solution play_arrow

• question_answer79)
  Which of the following figures represents the electric field lines due to a single negative charge?
  A)
             done clear
  B)
  done clear
  C)
  done clear
  D)
  done clear
  View Solution play_arrow

• question_answer80)
  Which of the following statements is not true about electric field lines?
  A)
  Electric field lines start from positive charge and end at negative charge done clear
  B)
  Two electric field lines can never cross each other done clear
  C)
  Electrostatic field lines do not form any closed loops done clear
  D)
  Electric field lines cannot be taken as continuous curve done clear
  View Solution play_arrow

• question_answer81)
  Figures shows the electric field Lines around three point charges A, B and C. Which of the following charges are positive?
  A)
  Only A done clear
  B)
  Only C done clear
  C)
  Both A and C done clear
  D)
  Both B and C done clear
  View Solution play_arrow

• question_answer82)
  Which of the following represents the electric field lines due to a combinations of two negative charges?
  A)
  done clear
  B)
  done clear
  C)
  done clear
  D)
    done clear
  View Solution play_arrow

• question_answer83)
  Which of the following figure represents the electric field lines due to a combination of one positive and one negative charge?
  A)
    done clear
  B)
  done clear
  C)
  done clear
  D)
  done clear
  View Solution play_arrow

• question_answer84)

  Which of the following figures correctly shows the top view sketch of the electric field lines for a uniformly charged hollow cylinder as shown in figure?

   
  A)
  done clear
  B)
  done clear
  C)
  done clear
  D)
  done clear
  View Solution play_arrow

• question_answer85)
  A non-uniform electric field is represented by the diagram. At which of the following points the electric field is greatest in magnitude?
  A)
  A                      done clear
  B)
  B done clear
  C)
  C                      done clear
  D)
  D done clear
  View Solution play_arrow

• question_answer86)
  Which of the following curves represent electric field line correctly?
  A)
  done clear
  B)
  done clear
  C)
  done clear
  D)
  done clear
  View Solution play_arrow

• question_answer87)
  For a dipole, electric field lines are dense at the point located at:
  A)
  center of dipole       done clear
  B)
  one of the charges done clear
  C)
  outside the dipole   done clear
  D)
  perpendicular to dipole done clear
  View Solution play_arrow

• question_answer88)
  The SI unit of electric flux is:
  A)
  \[N{{C}^{-1}}{{m}^{2}}\]                 done clear
  B)
  \[NC{{m}^{-2}}\] done clear
  C)
  \[N{{C}^{-2}}{{m}^{2}}\]                 done clear
  D)
  \[N{{C}^{-1}}{{m}^{-2}}\] done clear
  View Solution play_arrow

• question_answer89)
  The dimensional formula of electric flux is:
  A)
  \[\left[ {{M}^{1}}{{L}^{1}}{{T}^{-2}} \right]\]          done clear
  B)
  \[\left[ {{M}^{1}}{{L}^{3}}{{T}^{-3}}{{A}^{-1}} \right]\] done clear
  C)
  \[\left[ {{M}^{2}}{{L}^{2}}{{T}^{-2}}{{A}^{-2}} \right]\]   done clear
  D)
  \[\left[ {{M}^{1}}{{L}^{-3}}{{T}^{3}}{{A}^{1}} \right]\] done clear
  View Solution play_arrow

• question_answer90)
  Electric flux will be maximum when:
  A)
  electric field and area are perpendicular to each other done clear
  B)
  electric field and area are parallel to each other done clear
  C)
  electric field and area are at an angle other than \[0{}^\circ \] and \[90{}^\circ \] done clear
  D)
  None of the above done clear
  View Solution play_arrow

• question_answer91)
  In case of a cube of 10 cm length. Electric flux is minimum for which of the case:
  A)
  Charge of 2 C is placed at the intersection point of diagonals done clear
  B)
  Charge of 1 C is placed at the center of cube done clear
  C)
  Charge of 2 C is placed outside the sphere done clear
  D)
  Charge of 1 C is placed on one of the sides done clear
  View Solution play_arrow

• question_answer92)
  A point charge q is placed at a distance a/I directly above the centre of a square of side a. The electric flux through the square is:
  A)
  \[\frac{q}{{{\varepsilon }_{0}}}\]                                   done clear
  B)
  \[\frac{q}{\pi {{\varepsilon }_{0}}}\] done clear
  C)
  \[\frac{q}{4{{\varepsilon }_{0}}}\]                                 done clear
  D)
  \[\frac{q}{6{{\varepsilon }_{0}}}\] done clear
  View Solution play_arrow

• question_answer93)
  A circular plane sheet of radius 10 cm is placed in a uniform electric field of\[5\times {{10}^{5}}\text{ }N{{C}^{-1}}\], making an angle of \[60{}^\circ \]with the field. The electric flux through the sheet is:
  A)
  \[1.36\times {{10}^{2}}N{{m}^{2}}{{C}^{-1}}\] done clear
  B)
  \[1.36\times {{10}^{4}}\,N{{m}^{2}}{{C}^{-1}}\] done clear
  C)
  \[0.515\,\times {{10}^{2}}\,N{{m}^{2}}{{C}^{-1}}\] done clear
  D)
  \[0.515\times {{10}^{4}}\,\,N{{m}^{2}}{{C}^{-1}}\] done clear
  View Solution play_arrow

• question_answer94)
  A uniform electric field \[E=2\times {{10}^{3}}\,N{{C}^{-1}}\]is acting along the positive X-axis. The flux of this field through a square of 10 cm on a side whose plane is parallel to the y-z plane is:
  A)
  \[20\,N{{C}^{-1}}{{m}^{2}}\]                       done clear
  B)
  \[30\,N{{C}^{-1}}{{m}^{2}}\] done clear
  C)
  \[10\,N{{C}^{-1}}{{m}^{2}}\]                       done clear
  D)
  \[40\,N{{C}^{-1}}{{m}^{2}}\] done clear
  View Solution play_arrow

• question_answer95)
  In a region where intensity of electric field is \[5\,N{{C}^{-1}}\]40 electric field lines are crossing per square metre. The number of electric field lines crossing per square metre where intensity of electric field is\[10\,N{{C}^{-1}}\], will be:
  A)
  20                     done clear
  B)
  80      done clear
  C)
  100                               done clear
  D)
  200 done clear
  View Solution play_arrow

• question_answer96)
  Which of the following is a property of electric dipole:
  A)
  It is a vector quantity done clear
  B)
  Dipole moment is directed from negative charge to positive charge done clear
  C)
  Net charge of electric dipole is zero done clear
  D)
  All of the above done clear
  View Solution play_arrow

• question_answer97)
  Which of the following statements about dipole moment is not true?
  A)
  The dimensions of dipole moment is [LTA] done clear
  B)
  The unit of dipole moment is Cm done clear
  C)
  Dipole moment is a vector quantity and directed from negative to positive charge done clear
  D)
  Dipole moment is a scalar quantity and has magnitude equal to the potential energy of the system of charges done clear
  View Solution play_arrow

• question_answer98)
  In case of dipole, which of the following quantity is inversely proportional to cube of distance between the charges:
  A)
  Electric flux done clear
  B)
  Electric field done clear
  C)
  Force at the centre of dipole done clear
  D)
  Force at the point perpendicular to dipole done clear
  View Solution play_arrow

• question_answer99)
  What will be the value of electric field at the centre of the electric dipole?
  A)
  Zero done clear
  B)
  Equal to the electric field due to one charge at the centre done clear
  C)
  Twice the electric field due to one charge at the centre done clear
  D)
  Half the value of electric field due to one charge at the centre done clear
  View Solution play_arrow

• question_answer100)
  Figure shows electric field lines in which an electric dipole                                                                                      is placed at shown. Which of the following statements is correct?                                                                                                             (NCERT EXEMPLAR)
  A)
  The dipole will not experience any force done clear
  B)
  The dipole will experience a force towards right done clear
  C)
  The dipole will experience a force towards left done clear
  D)
  The dipole will experience a force upwards done clear
  View Solution play_arrow

• question_answer101)
            The necessary condition for the ratio of electric field intensity due to an electric dipole of dipole Length la at its axial point to its equatorial point is 2 : 1 is:
  A)
  \[r>>a\] , where r is the distance from the midpoint of the dipole to the concerned point done clear
  B)
  \[r<<a\] , where r is the distance from the midpoint of the dipole to the concerned point done clear
  C)
  r = a, where r is the distance from the midpoint of the dipole to the concerned point done clear
  D)
  None of these done clear
  View Solution play_arrow

• question_answer102)
  The ratio of electric field due to an electric dipole on its axis and on the perpendicular bisector of the dipole is:
  A)
  1 : 2 done clear
  B)
  2 : 1 done clear
  C)
  1 : 4                              done clear
  D)
  4 : 1 done clear
  View Solution play_arrow

• question_answer103)
    A point charge is situated at an axial point of a small electric dipole at a large distance from it. The charge experiences a force F. If the distance of the charge is doubled, the force acting on the charge will become:
  A)
  2F                     done clear
  B)
  F/2    done clear
  C)
  F/4                    done clear
  D)
  (d) F/8 done clear
  View Solution play_arrow

• question_answer104)
  An electric dipole of dipole moment \[20\times {{10}^{6}}\,Cm\] is enclosed by a closed surface. The net flux coming out of the surface is:
  A)
  \[10\times {{10}^{-3}}\]                         done clear
  B)
  \[20\times {{10}^{-6}}\] done clear
  C)
  \[\frac{q}{2}\]                                     done clear
  D)
  0 done clear
  View Solution play_arrow

• question_answer105)
  Two charges \[+20\mu C\]  and \[-20\,\mu \,C\] are placed 10 mm apart. The electric field at point P, on the axis of the dipole 10 cm away from its centre O on the side of the positive charge is:
  A)
  \[8.6\times {{10}^{9}}N{{C}^{-1}}\] done clear
  B)
  \[4.1\times {{10}^{6}}\,N{{C}^{-1}}\] done clear
  C)
  \[3.6\,\times {{10}^{6}}N{{C}^{-1}}\]             done clear
  D)
  \[4.6\times {{10}^{5}}N{{C}^{-1}}\] done clear
  View Solution play_arrow

• question_answer106)
  Two points charges of \[1\mu C\] and \[-1\mu \,C\]are separated by a distance of 100  A point P is at a distance of 10 cm from the midpoint and on the perpendicular bisector of the line joining the two charges. The electric field at P will be
  A)
  \[9\,N{{C}^{-1}}\]                         done clear
  B)
  \[0.9\,N{{C}^{-1}}\] done clear
  C)
  \[90\,N{{C}^{-1}}\]                         done clear
  D)
  \[0.09\,N{{C}^{-1}}\] done clear
  View Solution play_arrow

• question_answer107)
  Shown in the figure is a shell made of a conductor. It has inner radius a and outer radius b, and carries charge Q. At its centre is a dipole p as shown. In this case:
  A)
  surface charge density on the inner surface of the shell is zero even/where done clear
  B)
  surface charge density on the inner surface is uniform and equal                                                         \[\frac{\left( Q/2 \right)}{4\pi {{a}^{2}}}\] to done clear
  C)
  electric field outside the shell is the same as that of a point charge at the centre of the shell done clear
  D)
  surface charge density on the outer surface depends on                                                                 \[\left| \overrightarrow{p} \right|\] . done clear
  View Solution play_arrow

• question_answer108)
  If an electric dipole is placed in a uniform electric field, it experiences:
  A)
  torque only done clear
  B)
  net force only done clear
  C)
  both torque and net force done clear
  D)
  neither torque nor net force done clear
  View Solution play_arrow

• question_answer109)
  Torque induced by an external electric field on a dipole is maximum when:
  A)
  dipole moment and electric field are parallel            done clear
  B)
  dipole moment and electric field are perpendicular done clear
  C)
  dipole moment and electric field are at angle of                                                                              \[180{}^\circ\] done clear
  D)
  None of the above done clear
  View Solution play_arrow

• question_answer110)
  In the case of dipole subjected to external electric field that gains torque, which of the following angle represents an unstable equilibrium:
  A)
                                                                                \[0{}^\circ\] done clear
  B)
                                                                               \[45{}^\circ\]      done clear
  C)
                                                                               \[90{}^\circ\]                         done clear
  D)
                                                                               \[180{}^\circ\] done clear
  View Solution play_arrow

• question_answer111)
  An electric dipole is placed in an uniform electric field with the dipole axis making an angle                                                                                  \[\theta\] with the direction of the electric field. The orientation of the dipole for stable equilibrium is:
  A)
                                                                              \[\frac{\pi }{6}\]                                     done clear
  B)
                                                                              \[\frac{\pi }{3}\]   done clear
  C)
  0                                  done clear
  D)
                                                                              \[\frac{\pi }{2}\] done clear
  View Solution play_arrow

• question_answer112)
  An electric dipole of dipole moment p is placed in a uniform external electric field E. Then the:
  A)
  torque experienced by the dipole is                                                        \[\overrightarrow{E}\times \overrightarrow{p}\] done clear
  B)
  torque is zero, if                                                                         \[\overrightarrow{p}\] is perpendicular to                                                                         \[\overrightarrow{E}\] done clear
  C)
  torque is maximum, if                                                                         \[\overrightarrow{p}\] is perpendicular to                                                                         \[\overrightarrow{E}\]   done clear
  D)
  potential energy is maximum, if                                                                         \[\overrightarrow{p}\]  is parallel to                                                                         \[\overrightarrow{E}\] done clear
  View Solution play_arrow

• question_answer113)
  An electric dipole placed in a non-uniform electric field can experience:                                              (CBSE 2020)
  A)
  a force but not a torque done clear
  B)
  a torque but not a force done clear
  C)
  always a force and a torque done clear
  D)
  neither a force nor a torque done clear
  View Solution play_arrow

• question_answer114)
  Two equal and opposite charges                                                                     \[2\times {{10}^{-10}}C\] are placed at a distance of 1 cm forming a dipole and are placed in an electric field                                                                    \[2\times {{10}^{5}}\,N/C\] , maximum torque on dipole is:
  A)
                                                               \[2\sqrt{2}\times {{10}^{-6}}\,Nm\] done clear
  B)
                                                                      \[8\times {{10}^{8}}Nm\] done clear
  C)
                                                                    \[4\times {{10}^{-9}}\,Nm\] done clear
  D)
                                                                    \[4\times {{10}^{-7}}\,Nm\] done clear
  View Solution play_arrow

• question_answer115)
  An electric dipole is placed at an angle of                                                                              \[30{}^\circ\]  with an electric field of intensity                                                            \[2\times {{10}^{5}}\,N{{C}^{-1}}\] . It experiences a torque equal to 4 Nm. The charge on the dipole if the dipole length is 2 cm is:
  A)
  B mC                            done clear
  B)
  4 mC   done clear
  C)
  6 mC                            done clear
  D)
  2 mC done clear
  View Solution play_arrow

• question_answer116)
  Two small balls each having a positive charge Q Coulombs are suspended by two insulating strings of equal length L meters from a hook fixed to a stand. The whole setup is taken in a satellite into space, where there is no gravity. What is the angle between the string and tension in the string?
  A)
                  \[180{}^\circ ,\,\frac{1}{4\pi {{\varepsilon }_{0}}}\frac{{{Q}^{2}}}{{{\left( 2L \right)}^{2}}}\]             done clear
  B)
                           \[90{}^\circ ,\,\frac{1}{4\pi {{\varepsilon }_{0}}}\frac{{{Q}^{2}}}{{{L}^{2}}}\] done clear
  C)
                           \[180{}^\circ ,\frac{1}{4\pi {{\varepsilon }_{0}}}\frac{{{Q}^{2}}}{2{{L}^{2}}}\] done clear
  D)
                                          \[180{}^\circ ,\frac{1}{4\pi {{\varepsilon }_{0}}}\frac{Q}{4L}\] done clear
  View Solution play_arrow

• question_answer117)
              When a comb rubbed with dry hair attracts pieces of paper. This is because the:
  A)
  comb polarises the piece of paper done clear
  B)
  comb induces a net dipole moment opposite to the direction of field done clear
  C)
  electric field due to the comb is uniform done clear
  D)
  comb induces a net dipole moment perpendicular to the direction of field                                           done clear
  View Solution play_arrow

• question_answer118)
  What is the dimension of volume charge density:
  A)
                                                    \[\left[ {{A}^{2}}{{L}^{-3}}{{T}^{2}} \right]\]                         done clear
  B)
                                                                    \[\left[ A{{L}^{-3}}T \right]\] done clear
  C)
                                                                    \[\left[ A{{L}^{-2}}T \right]\]                         done clear
  D)
                                                    \[\left[ {{A}^{2}}{{L}^{-2}}{{T}^{2}} \right]\] done clear
  View Solution play_arrow

• question_answer119)
  What is the unit of linear charge density:
  A)
  Unitless                          done clear
  B)
  C/m     done clear
  C)
  C-m                              done clear
  D)
  C done clear
  View Solution play_arrow

• question_answer120)
  If                                                                                  \[\sigma\] = Surface charge density,                                                                               \[\varepsilon\]  = electric permittivity, then dimension of                                                                   \[\frac{\sigma }{\varepsilon }\]
  A)
  electric force done clear
  B)
  electric field intensity done clear
  C)
  pressure done clear
  D)
  electric charge done clear
  View Solution play_arrow

• question_answer121)
  Match the following and find the correct option:

  	Column - I		Column - II
  A.	Linear charge density	p.	\[\frac{Ch\arg e}{Volume}\]
  B.	Surface charge density	q.	\[\frac{Ch\arg e}{Length}\]
  C.	Volume charge density	r.	\[\frac{Ch\arg e}{Area}\]

  A)
  A-q, B-r, C-p           done clear
  B)
  A-p, B-r, C-p done clear
  C)
  A-r, B-p, C-q           done clear
  D)
  A-r, B-q, C-p done clear
  View Solution play_arrow

• question_answer122)
  Electric field at a point of distance r from a uniformly charged wire of infinite length having Linear charge density                                                                                 \[\lambda\] is directly proportional to:
  A)
                                                                               \[{{r}^{-1}}\]                                     done clear
  B)
  r done clear
  C)
                                                                               \[{{r}^{2}}\]                                     done clear
  D)
                                                                               \[{{r}^{-2}}\] done clear
  View Solution play_arrow

• question_answer123)
  The surface considered for Gauss's law is called:        
  A)
  closed surface        done clear
  B)
  spherical surface done clear
  C)
  Gaussian surface     done clear
  D)
  plane surface done clear
  View Solution play_arrow

• question_answer124)
  If \[\oint{_{s}}\overrightarrow{E}.\,d\,\,\overrightarrow{S}\,=0\]over a surface, then:
  A)
  the electric field inside the surface and on it is zero done clear
  B)
  the electric field inside the surface is necessarily uniform done clear
  C)
  all charges must be outside the surface                done clear
  D)
  None of the above     done clear
  View Solution play_arrow

• question_answer125)
  The electric flux through a closed Gaussian surface depends upon:                                                     (CBSE 2020)
  A)
  net charge enclosed and permittivity of the medium done clear
  B)
  (b) net charge enclosed, permittivity of the medium and the size of the Gaussian surface done clear
  C)
  net charge enclosed only done clear
  D)
  permittivity of the medium only done clear
  View Solution play_arrow

• question_answer126)
  If the net electric flux through a closed surface is zero, then we can infer that:                          (C8SE 2020)
  A)
  no net charge is enclosed by the surface       done clear
  B)
  uniform electric field exists within the surface done clear
  C)
  electric potential varies from point to point inside the surface done clear
  D)
  charge is present inside the surface done clear
  View Solution play_arrow

• question_answer127)
  The electric flux through the surface:                                                                      (NCEKT EXEMPLAR)                 
  A)
  in figure (iv) is the largest done clear
  B)
  in figure (iii) is the least done clear
  C)
  in figure (ii) is same as in figure (iii) but is smaller than figure (iv) done clear
  D)
  is the same for all the figures done clear
  View Solution play_arrow

• question_answer128)
  Five charges \[{{q}_{1}},\,{{q}_{2}}\]\[{{q}_{3}},{{q}_{4}}\] and \[{{q}_{5}}\]are fixed at their positions as shown in figure, S is a Gaussian surface. The Gauss's law is given by \[\oint{_{s}}\overrightarrow{E}\,.\,d\,\overrightarrow{S}=\frac{q}{{{\varepsilon }_{0}}}\] Which of the following statement is correct?                                                            (NCERT EXEMPLAR)
  A)
  \[\overrightarrow{E}\]on the LHS of the above equation will have a contribution from \[{{q}_{1}}.\,{{q}_{5}}\]and \[{{q}_{3}}\]while q on the RH5 will have a contribution from \[{{q}_{1}}\]and \[{{q}_{4}}\] only done clear
  B)
  \[\overrightarrow{E}\] on the LHS of the above equation will have a contribution from all charges while q on the RH5 will have a contribution from \[{{q}_{2}}\]and \[{{q}_{4}}\] only done clear
  C)
  \[\overrightarrow{E}\] on the LHS of the above equation will have a contribution from all charges while q on the RH5 will have a contribution from \[{{q}_{1}},\,{{q}_{3}}\]and \[{{q}_{5}}\] only done clear
  D)
  Both \[\overrightarrow{E}\]on the LH5 and q on the RHS will have contribution from \[{{q}_{2}}\]and \[{{q}_{4}}\]only done clear
  View Solution play_arrow

• question_answer129)
  A sphere encloses an electric dipole within it. The total flux across the sphere is:
  A)
  zero done clear
  B)
  half that due to a single charge done clear
  C)
  double that due to a single charge done clear
  D)
  dependent on the position of dipole done clear
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• question_answer130)
  Which of the following statements is not true about Gauss's law?
  A)
  Gauss's law is true for any closed surface done clear
  B)
  The term q on the right side of Gauss's law includes the sum of all charges enclosed by the surface done clear
  C)
  Gauss's law is not much useful in calculating electrostatic field when the system has some symmetry done clear
  D)
  Gauss's law is based on the inverse square dependence on distance contained in the coulomb's law done clear
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• question_answer131)
  The electric flux through a cube of side 1 cm which encloses an electric dipole is:
  A)
  \[\frac{q}{6{{\varepsilon }_{0}}}\]         done clear
  B)
  \[\frac{3q}{{{\varepsilon }_{0}}}\] done clear
  C)
  0                                  done clear
  D)
  \[\frac{q}{3{{\varepsilon }_{0}}}\] done clear
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• question_answer132)
  A point charge \[4\mu C\]is at the centre of a cubic Gaussian surface 10 cm on edge. Net electric flux through the surface is:
  A)
  \[2.5\times {{10}^{5}}N{{m}^{2}}{{C}^{-1}}\] done clear
  B)
  \[4.5\times {{10}^{5}}N{{m}^{2}}{{C}^{-1}}\] done clear
  C)
  \[4.5\times {{10}^{5}}N{{m}^{2}}{{C}^{-1}}\] done clear
  D)
  \[2.5\times {{10}^{6}}N{{m}^{2}}{{C}^{-1}}\] done clear
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• question_answer133)
  The electric field components in the given figure are \[{{E}_{x}}=\alpha {{x}^{1/2}}\], \[{{E}_{y}}={{E}_{z}}=0\] which \[\alpha =800\,N{{C}^{-1}}{{m}^{-1/2}}\]. The charge within the cube, if net flux through the cube is \[1.05\,N{{m}^{2}}{{C}^{-1}}\]is (assume, a =0.1 m):
  A)
  \[9.27\times {{10}^{-12}}C\]     done clear
  B)
  \[9.27\times {{10}^{12}}C\] done clear
  C)
  \[6.97\times {{10}^{-12}}C\] done clear
  D)
  \[6.97\times {{10}^{12}}C\] done clear
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• question_answer134)
  The total flux through the faces of the cube with side of length a, if a charge q is placed at corner A of the cube is:
  A)
  \[\frac{q}{8{{\varepsilon }_{0}}}\]                     done clear
  B)
  \[\frac{q}{4{{\varepsilon }_{0}}}\] done clear
  C)
  \[\frac{q}{2{{\varepsilon }_{0}}}\]                                 done clear
  D)
  \[\frac{q}{{{\varepsilon }_{0}}}\] done clear
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• question_answer135)
  A cylinder of radius R and length L is placed in a uniform electric field E parallel to the cylinder axis. The total flux for the surface of the cylinder is given by:
  A)
  \[2\pi {{R}^{2}}E\]                  done clear
  B)
  \[\frac{{{R}^{2}}}{E}\] done clear
  C)
  \[\frac{\pi {{R}^{2}}}{E}\]                   done clear
  D)
  zero done clear
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• question_answer136)
  The number of electric line of forces that radiated outward from 2 C of charge in vacuum is:
  A)
  \[1.13\times {{10}^{11}}\]                    done clear
  B)
  \[1.13\times {{10}^{13}}\] done clear
  C)
  \[2.26\times {{10}^{11}}\]                    done clear
  D)
  \[2.26\times {{10}^{13}}\] done clear
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• question_answer137)
  A point charge \[+20\mu C\] is at a distance 6 cm directly above the centre of a square of side 12 cm as shown in figure. The magnitude of electric flux through the square is:
  A)
  \[2.5\times {{10}^{6}}N{{m}^{2}}{{C}^{-1}}\] done clear
  B)
  \[3.8\times {{10}^{5}}N{{m}^{2}}{{C}^{-1}}\] done clear
  C)
  \[4.2\times {{10}^{5}}N{{m}^{2}}{{C}^{-1}}\] done clear
  D)
  \[2.9\times {{10}^{6}}N{{m}^{2}}{{C}^{-1}}\] done clear
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• question_answer138)
  Electric field is independent of distance of the given surface and charge in which of the case:
  A)
  Infinitely long uniformly charged wire done clear
  B)
  infinitely large uniformly charged plane sheet          done clear
  C)
  Uniformly charged spherical shell          done clear
  D)
  None of the above     done clear
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• question_answer139)
  Cylindrical Gaussian surface is used to calculate electric field intensity for:
  A)
  point charge done clear
  B)
  hollow sphere done clear
  C)
  infinitely plane sheet  done clear
  D)
  infinitely long charged wire done clear
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• question_answer140)
  According to Gauss Law electric field on infinitely long straight wire is proportional to:
  A)
  r                                   done clear
  B)
  \[\frac{1}{{{r}^{2}}}\] done clear
  C)
  \[\frac{1}{{{r}^{3}}}\]                         done clear
  D)
  \[\frac{1}{r}\] done clear
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• question_answer141)
  Two infinitely long parallel conducting plates having surface charge densities \[+\,\sigma \] and \[-\,\sigma \] respectively, are separated by a small distance. The medium between the plates is vacuum. If \[{{\varepsilon }_{0}}\]is the dielectric permittivity of vacuum, then the electric field in the region between the plates:
  A)
  \[0\,v/m\]                       done clear
  B)
  \[\frac{\sigma }{2{{\varepsilon }_{0}}}v/m\] done clear
  C)
  \[\frac{\sigma }{{{\varepsilon }_{0}}}v/m\]                     done clear
  D)
  \[\frac{2\sigma }{{{\varepsilon }_{0}}}v/m\] done clear
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• question_answer142)
  Above an infinitely large plane carrying a charge density'\[\sigma '\] an electric field points up and is equal to \[\frac{\sigma }{2{{\varepsilon }_{0}}}\]. What is the magnitude and direction of electric field below the plane?
  A)
  \[\frac{\sigma }{2{{\varepsilon }_{0}}}\]downwards     done clear
  B)
  \[\frac{\sigma }{2{{\varepsilon }_{0}}}\]upwards done clear
  C)
  \[\frac{\sigma }{2{{\varepsilon }_{0}}}\]downwards     done clear
  D)
  \[\frac{\sigma }{2{{\varepsilon }_{0}}}\]upwards done clear
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• question_answer143)
  Two large, thin metal plates are parallel and close to each other. On their inner faces, the plates have surface charge densities of opposite signs and of magnitude \[16\times {{10}^{-22}}\,C{{m}^{-2}}\]. The electric field between the plate is:
  A)
  \[1.8\times {{10}^{-10}}N{{C}^{-1}}\] done clear
  B)
  \[1.9\times {{10}^{-10}}N{{C}^{-1}}\] done clear
  C)
  \[1.6\times {{10}^{-10}}N{{C}^{-1}}\] done clear
  D)
  \[1.5\times {{10}^{-10}}N{{C}^{-1}}\] done clear
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• question_answer144)
  Two large thin metal plates are parallel and close to each other. On their inner faces, the plates have surface charge densities   of   opposite   signs   and   magnitude\[27\times {{10}^{-22}}C{{m}^{-2}}\]. The electric field \[\overrightarrow{E}\] in region II in between the plate is:
  A)
  \[4.25\times {{10}^{-8}}N{{C}^{-1}}\] done clear
  B)
  \[6.28\times {{10}^{-10}}N{{C}^{-1}}\] done clear
  C)
  \[3.05\times {{10}^{-10}}N{{C}^{-1}}\] done clear
  D)
  \[5.03\times {{10}^{-10}}N{{C}^{-1}}\] done clear
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• question_answer145)
  Consider a thin spherical shell of radius R consisting of uniform surface charge density. The electric field at a point outside the shell at a distance x from its centre is:
  A)
  inversely proportional to \[\sigma \] done clear
  B)
  directly proportional to \[{{x}^{2}}\] done clear
  C)
  directly proportional to R done clear
  D)
  inversely proportional to \[{{x}^{2}}\] done clear
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• question_answer146)
                          The electric field at a distance R due to charge q is E. If the same charge is placed on the copper spherical shell of radius R, the electric field strength at the surface of the conductor will be:
  A)
  \[\frac{E}{4}\]                           done clear
  B)
  \[\frac{E}{2}\] done clear
  C)
  E                                  done clear
  D)
  2E done clear
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• question_answer147)
  A point charge \[+q\], is placed at a distance dfrom an isolated conducting plane. The field at a point P on the other side of the plane is:                                                                                                             (NCERT EXEMPLAR)
  A)
  directed perpendicular to the plane and away from the plane   done clear
  B)
  directed perpendicular to the plane but towards the plane done clear
  C)
  directed radially away from the point charge done clear
  D)
  directed radially towards the point charge              done clear
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