10th Class Science Electricity and Circuits Question Bank

done Electricity Total Questions - 227

• question_answer1)
  An electric charge on a body produces
  A)
   a magnetic field only done clear
  B)
   an electric field only   done clear
  C)
   both [a] and [b] done clear
  D)
   none of these done clear
  View Solution play_arrow

• question_answer2)
  There is no flow of current between two charged bodies when connected because, they have the same
  A)
   quantity of charge done clear
  B)
   potential   done clear
  C)
   capacity done clear
  D)
   ratio of potential per unit charge done clear
  View Solution play_arrow

• question_answer3)
  If a charged body attracts another body, then charge on the other body
  A)
   must be negative done clear
  B)
   must be positive done clear
  C)
   must be zero done clear
  D)
   may be negative or positive or zero   done clear
  View Solution play_arrow

• question_answer4)
  Electromotive force represents
  A)
   force done clear
  B)
   energy done clear
  C)
   energy per unit charge   done clear
  D)
   current done clear
  View Solution play_arrow

• question_answer5)
  Unit of e. m. f. of a cell is
  A)
   dyne                     done clear
  B)
          volt   done clear
  C)
   ampere           done clear
  D)
          joule done clear
  View Solution play_arrow

• question_answer6)
  Commonly used safety fuse wire is made of
  A)
   copper done clear
  B)
   lead done clear
  C)
   nickel done clear
  D)
   an alloy of tin and lead   done clear
  View Solution play_arrow

• question_answer7)
  Kilowatt hour is the unit of
  A)
   power            done clear
  B)
          energy   done clear
  C)
   impulse           done clear
  D)
          force done clear
  View Solution play_arrow

• question_answer8)
  Work done in moving an electric charge q in an electric field does not depend upon
  A)
   magnitude of the charge done clear
  B)
   potential difference between two points done clear
  C)
   mass of the particle   done clear
  D)
   all of these done clear
  View Solution play_arrow

• question_answer9)
  If a unit charge is taken from one point to another over an equipotential surface, then
  A)
   work is done on the charge done clear
  B)
   work is done by the charge   done clear
  C)
   work done on the charge is constant done clear
  D)
   no work is done done clear
  View Solution play_arrow

• question_answer10)
  Materials which allow larger currents to flow through them are
  A)
   insulators done clear
  B)
   semi-conductors   done clear
  C)
   conductors done clear
  D)
   alloys done clear
  View Solution play_arrow

• question_answer11)
  Conventionally, the direction of the current is taken as the direction of flow
  A)
   to negative charge done clear
  B)
   the direction of flow of atoms done clear
  C)
   of molecules done clear
  D)
   of positive charge   done clear
  View Solution play_arrow

• question_answer12)
  Ratio of the electrostatic to gravitational force between two electrons placed at a certain distance in air will be \[({{m}_{e}}=9.1\,\times \,{{10}^{-31}}Kg,\,\]\[\,e=1.6\times {{10}^{-19}}C\,and\,G\,=6.6\times {{10}^{-11}}N{{m}^{2}}/k{{g}^{2}})\]
  A)
   \[4.2\times {{10}^{42}}\]   done clear
  B)
   \[4.2\times {{10}^{-42}}\] done clear
  C)
   \[\text{2}\text{.4 }\times \text{ 1}0\text{24}\] done clear
  D)
   \[\text{2}.\text{4 }\times \text{ 1}0.\text{24}\] done clear
  View Solution play_arrow

• question_answer13)
  Three charges \[4q\], \[Q\] and q are placed in a straight line of length \[l\] at points distant 0, 1/2 and \[l\]respectively. What should be \[Q\] in order to make the net force on q equal to zero?
  A)
   \[-4q\]                 done clear
  B)
          \[-2q\] done clear
  C)
   \[-\frac{q}{2}\]                 done clear
  D)
          \[-q\]   done clear
  View Solution play_arrow

• question_answer14)
  In the circuit, reading of the voltmeter V will be
  A)
   \[4\,\,V\]                              done clear
  B)
          \[2\,\,V\] done clear
  C)
   \[6\,\,V\]                            done clear
  D)
          \[3\,\,V\] done clear
  View Solution play_arrow

• question_answer15)
  if length of a wire is doubled and its cross-section is also doubled, then the resistance
  A)
   increase eight times done clear
  B)
   decrease four times done clear
  C)
   become four times done clear
  D)
   remain unchanged   done clear
  View Solution play_arrow

• question_answer16)
  In the given figure, distance [d] between conductors carrying currents \[{{I}_{1}}\] and \[{{I}_{2}}\] is varied. Which of the following graphs correctly represents the variation of force (F) between the conductors and distance [d]?
  A)
    done clear
  B)
  done clear
  C)
  done clear
  D)
   None of these done clear
  View Solution play_arrow

• question_answer17)
  A magnetic field cannot exert any force on a
  A)
   moving magnet done clear
  B)
   stationary magnet done clear
  C)
   moving charge done clear
  D)
   stationary charge   done clear
  View Solution play_arrow

• question_answer18)
  Force between the two parallel wires carrying currents has been used to define
  A)
   ampere             done clear
  B)
          coulomb done clear
  C)
   volt                       done clear
  D)
          watt done clear
  View Solution play_arrow

• question_answer19)
  Unit of specific resistance is
  A)
   ohm                      done clear
  B)
          mho done clear
  C)
   ohm-metre         done clear
  D)
          ohm per metre done clear
  View Solution play_arrow

• question_answer20)
  Electron volt is the unit of
  A)
   energy              done clear
  B)
   potential difference done clear
  C)
   charge            done clear
  D)
          charge to mass done clear
  View Solution play_arrow

• question_answer21)
  If a man has five resistors each of value \[\frac{1}{5}\Omega \] then is the maximum resistance he can obtain by connecting them, is
  A)
   \[1\,\Omega \]                    done clear
  B)
          \[5\,\Omega \] done clear
  C)
   \[\,\frac{1}{2}\Omega \]                  done clear
  D)
          \[\frac{2}{5}\Omega \] done clear
  View Solution play_arrow

• question_answer22)
  In the above questions, the minimum resistance that one can obtain by connecting all the five resistances, is
  A)
   \[\frac{1}{10}\Omega \]              done clear
  B)
          \[\frac{1}{5}\Omega \] done clear
  C)
   \[\frac{1}{50}\Omega \]               done clear
  D)
          \[\frac{1}{25}\Omega \]   done clear
  View Solution play_arrow

• question_answer23)
  If the force between two charged objects is to be left unchanged even through the charge on one of the objects is halved, keeping the other the same, then the original distance of separation 'd' should be
  A)
   \[d\sqrt{2}\]                     done clear
  B)
          \[\frac{d}{\sqrt{2}}\]   done clear
  C)
   \[\frac{\sqrt{2}}{d}\]                done clear
  D)
          \[2d\] done clear
  View Solution play_arrow

• question_answer24)
  A suitable unit for expressing the strength of electric field is
  A)
   V/C                         done clear
  B)
          C/m done clear
  C)
   N/C                       done clear
  D)
          C/N done clear
  View Solution play_arrow

• question_answer25)
  1 volt equals
  A)
   1 joule   done clear
  B)
   1 joule per coulomb done clear
  C)
   1 coulomb per metre done clear
  D)
   1 newton per coulomb done clear
  View Solution play_arrow

• question_answer26)
  Which of the following networks yields minimum current?
  A)
      done clear
  B)
    done clear
  C)
    done clear
  D)
    done clear
  View Solution play_arrow

• question_answer27)
  Three charges \[-q\],\[Q\] and \[-q\] are placed at equal distances on a straight line. If the total potential energy of the system of three charges is zero, then the ratio \[Q\]: \[q\] is
  A)
   1 : 2                  done clear
  B)
                          2 : 1 done clear
  C)
   1 : 1                done clear
  D)
                          1 : 4 done clear
  View Solution play_arrow

• question_answer28)
  In the given network, the resistance between A and B is
  A)
   \[2\Omega \] done clear
  B)
   \[2\Omega \] done clear
  C)
   \[\frac{3}{2}\Omega \] done clear
  D)
   \[\frac{2}{3}\Omega \]   done clear
  View Solution play_arrow

• question_answer29)
  If two electrons are separated by a distance of \[0.\text{5}\overset{\circ }{\mathop{\text{A}}}\,\], then ratio of coulomb force and weight of electron is approximately
  A)
  \[\text{1}{{0}^{\text{16}}}\]                      done clear
  B)
          \[\text{1}{{0}^{\text{18}}}\] done clear
  C)
  \[\text{1}{{0}^{\text{2}0}}\]                       done clear
  D)
          \[\text{1}{{0}^{\text{22}}}\]   done clear
  View Solution play_arrow

• question_answer30)
  Two positively charged particles each of mass \[\text{1}.\text{7 }\times \text{ 1}{{0}^{-\text{27}}}\]kg and carrying a charge of \[\text{1}.\text{6 }\times \text{ 1}{{0}^{-\text{19}}}\]are placed at a distance r apart. If each one experiences a repulsive force equal to its weight, then r is
  A)
   1.17 m                  done clear
  B)
   1.71m done clear
  C)
   0.117m              done clear
  D)
          0.171m done clear
  View Solution play_arrow

• question_answer31)
  A particle of mass 2g and charge \[1\mu C\] is held at a distance of 1 m from a fixed charge of 1 \[mC\]. If the particle of released it will be repelled. Speed of the particle when it is at a distance of 10 m from the fixed charge is
  A)
   100 m/sec         done clear
  B)
          90 m/sec   done clear
  C)
   60 m/sec          done clear
  D)
          45 m/sec done clear
  View Solution play_arrow

• question_answer32)
  If a wire is stretched to double its length, then the resistance will become
  A)
   half                                       done clear
  B)
   double done clear
  C)
   one fourth        done clear
  D)
   four times   done clear
  View Solution play_arrow

• question_answer33)
  Which switch in the circuit when closed will produce short-circuiting?
  A)
   A              done clear
  B)
          B done clear
  C)
   C                            done clear
  D)
          None of these   done clear
  View Solution play_arrow

• question_answer34)
  The fact that current is associated with a magnetic field was discovered by
  A)
   operated              done clear
  B)
   Maxwell done clear
  C)
   Faraday          done clear
  D)
          Ohm done clear
  View Solution play_arrow

• question_answer35)
  Reciprocal of resistivity of a conductor is
  A)
   conductance       done clear
  B)
          capacitance done clear
  C)
   conductivity         done clear
  D)
          None of these done clear
  View Solution play_arrow

• question_answer36)
  The slope of current (\[I\]) versus voltage (\[V\]) is calf
  A)
   resistance            done clear
  B)
           resistivity             done clear
  C)
           conductivity        done clear
  D)
               conductance                  done clear
  View Solution play_arrow

• question_answer37)
  The slope of voltage (\[V\]) versus current (\[I\]) is called
  A)
   resistance                     done clear
  B)
   conductance       done clear
  C)
            resistivity             done clear
  D)
                 conductivity              done clear
  View Solution play_arrow

• question_answer38)
      With rise in temperature the resistance of germanium,
  A)
   increases done clear
  B)
   decreases   done clear
  C)
   remains the same done clear
  D)
   first increases then decreases done clear
  View Solution play_arrow

• question_answer39)
  Resistance of a straight conductor does not depend upon its
  A)
   shape of the cross-section   done clear
  B)
   temperature done clear
  C)
   material done clear
  D)
   length done clear
  View Solution play_arrow

• question_answer40)
  What is immaterial for an electric fuse wire?
  A)
   Its specific resistance done clear
  B)
   Its radius done clear
  C)
   Its length   done clear
  D)
   Current flowing through it done clear
  View Solution play_arrow

• question_answer41)
  When there is an electric current through a conducting wire along its length then an electric field must exist
  A)
   inside the wire but normal to it done clear
  B)
   inside the wire but parallel to it   done clear
  C)
   outside the wire but normal to it done clear
  D)
   outside the wire but parallel to it done clear
  View Solution play_arrow

• question_answer42)
  Two identical heater coils are connected in parallel the mains. If one of the coils breaks, then other coil
  A)
   will also not be heated done clear
  B)
   develop a higher temperature done clear
  C)
   develop a lower temperature done clear
  D)
   will develop the same amount of temperature  as before   done clear
  View Solution play_arrow

• question_answer43)
  A tap supplies water at \[22{}^\circ C\]. Aman takes 11 litre water per minute at \[37{}^\circ C\] from the geyser is  The power of geyser is
  A)
   525 W                   done clear
  B)
   1050 W   done clear
  C)
   1575 W              done clear
  D)
          2100 W done clear
  View Solution play_arrow

• question_answer44)
  When temperature of a conductor increases, its resistance
  A)
   increases            done clear
  B)
          decreases done clear
  C)
   remains the same           done clear
  D)
   none of these done clear
  View Solution play_arrow

• question_answer45)
  With rise the temperature, resistance of carbon
  A)
   increases done clear
  B)
   decreases   done clear
  C)
   remains the same done clear
  D)
   first increases then decreases done clear
  View Solution play_arrow

• question_answer46)
  With rise in temperature, resistance of a semiconductor material (germanium or silicon)
  A)
   increases done clear
  B)
   decreases   done clear
  C)
   remains the same done clear
  D)
   first increases then decreases done clear
  View Solution play_arrow

• question_answer47)
  In the Bohr's model of hydrogen atom, the electron moves around the nucleus in a circular orbit of radius \[\text{5 }\times \text{1}{{0}^{-\text{11}}}\] metres. If its time period is \[\text{1}.\text{5 }\times \text{ 1}{{0}^{-\text{16}}}\] sec, then current associated with the electron motion is
  A)
   zero                      done clear
  B)
          \[\text{1}.\text{6 }\times \text{ 1}{{0}^{-\text{19}}}\text{ A}\] done clear
  C)
   00.17 A             done clear
  D)
          \[\text{1}.0\text{7 }\times \text{1}{{0}^{-\text{3}}}\text{ A}\]   done clear
  View Solution play_arrow

• question_answer48)
  A steady beam of a-particles (q = 2e) travelling with constant kinetic energy 20 Me V carries a current \[0.25\mu \]A. If the beam is directed perpendicular to a plane surface, how many \[\alpha \]-particles strike the surface in 3 sees?
  A)
  \[\text{2}.\text{3}\times \text{l}{{0}^{\text{12}}}\]                           done clear
  B)
   \[\text{2}\text{.3 }\times \text{l}{{0}^{\text{19}}}\] done clear
  C)
  \[\text{2}.\text{3 }\times \text{ 1}{{0}^{\text{8}}}\]          done clear
  D)
          \[\text{2}\text{.3 }\times \text{ 1}{{0}^{\text{6}}}\] done clear
  View Solution play_arrow

• question_answer49)
   The terminal potential difference of a cell is greater than its e. m. f. when it is
  A)
   being discharged done clear
  B)
   in open circuit done clear
  C)
   being charged   done clear
  D)
   being either charged or discharged done clear
  View Solution play_arrow

• question_answer50)
  In Coulomb's law, the constant of proportionality K has the units
  A)
   N                                            done clear
  B)
   \[\text{N}{{\text{m}}^{\text{2}}}\] done clear
  C)
   \[\text{N}{{\text{C}}^{2}}\text{/}{{\text{m}}^{\text{2}}}\]         done clear
  D)
          \[\text{N}{{\text{m}}^{\text{2}}}/{{\text{C}}^{\text{2}}}\]   done clear
  View Solution play_arrow

• question_answer51)
  In comparing e. m. f. of two cells with the help of a potentiometer, at the balance point, the parent flowing through the wire is taken from
  A)
   one of these cells done clear
  B)
   both of these cells done clear
  C)
   the battery in the main circuit   done clear
  D)
   none of these done clear
  View Solution play_arrow

• question_answer52)
  A battery of 20 cells (each having e. m. f. 1.8 volt and internal resistance 0.1 ohm) is charged by 220 volts and the charging current is 15A. The resistance to be put in the circuit is
  A)
   10.27 ohms         done clear
  B)
          12.27 ohms done clear
  C)
   8.62 ohms        done clear
  D)
          16.24 ohms done clear
  View Solution play_arrow

• question_answer53)
  In the above question, total power obtained from the mains is
  A)
   6600W                 done clear
  B)
   3300W   done clear
  C)
   540W                    done clear
  D)
          276E done clear
  View Solution play_arrow

• question_answer54)
  In order to measure current in a resistance present in a circuit, the ammeter is connected
  A)
   in series   done clear
  B)
   in parallel done clear
  C)
   in series or parallel done clear
  D)
   nothing can be decided done clear
  View Solution play_arrow

• question_answer55)
  A current of 5 amperes is passing through a metallic wire of cross-sectional area\[\text{4 }\times \text{ 1}{{0}^{-\text{6}}}\text{ }{{\text{m}}^{\text{2}}}\]. If the density of the charge carrier in the wire is \[5\times {{10}^{26}}/{{m}^{3}},\] the drift velocity of the electrons is
  A)
   \[\frac{1}{8}m/s\]            done clear
  B)
          \[\frac{1}{16}m/s\] done clear
  C)
   \[\frac{1}{64}m/s\]          done clear
  D)
           \[\frac{1}{64}m/s\] done clear
  View Solution play_arrow

• question_answer56)
  How many turns of a nichrome wire 1 mm in diameter should be wound around a porcelain cylinder with radius 2.5 cm to obtain a furnace with a resistance of 2050? (p for nichrome = \[1.0\times {{10}^{6}}cm\])
  A)
   50                          done clear
  B)
          100   done clear
  C)
   150                        done clear
  D)
          200 done clear
  View Solution play_arrow

• question_answer57)
  The fixed resistance is called
  A)
   rheostat                              done clear
  B)
   resistor   done clear
  C)
   key                   done clear
  D)
          switch done clear
  View Solution play_arrow

• question_answer58)
  The variable resistance is called
  A)
   resistor              done clear
  B)
          rheostat   done clear
  C)
   open switch        done clear
  D)
          none of these done clear
  View Solution play_arrow

• question_answer59)
  If a resistance 5Q is connected in the left gap of a meter bridge and 15Q in the other gap then position of balancing point is
  A)
   10 cm done clear
  B)
   20 cm done clear
  C)
   25 cm   done clear
  D)
   75 cm done clear
  View Solution play_arrow

• question_answer60)
  Kirchhoff?s second law is based on the law of conservation of
  A)
   charge done clear
  B)
   energy   done clear
  C)
   momentum done clear
  D)
   sum of mass and energy done clear
  View Solution play_arrow

• question_answer61)
  The value of current i in the given circuit is
  A)
   Zero                      done clear
  B)
   \[5\,amp.\] done clear
  C)
   \[7\,amp.\]        done clear
  D)
          \[11\,amp.\]   done clear
  View Solution play_arrow

• question_answer62)
  In the given circuit, the voltmeter reading is
  A)
   0.5 volt            done clear
  B)
   1 volt done clear
  C)
   2 volt                 done clear
  D)
   4 volt               done clear
  View Solution play_arrow

• question_answer63)
  Device used for measuring potential difference is known as
  A)
   potentiometer done clear
  B)
   ammeter done clear
  C)
   voltmeter   done clear
  D)
   galvanometer done clear
  View Solution play_arrow

• question_answer64)
  Ohmic conductors
  A)
   obey Ohm's law   done clear
  B)
   do not obey Ohm's law done clear
  C)
   sometimes obey Ohm's law done clear
  D)
   none of these done clear
  View Solution play_arrow

• question_answer65)
  In a Wheat sone's bridge shown in the figure X = Y and A > B. The direction of the current between a and b will be
  A)
   from a to b          done clear
  B)
           from b to a            done clear
  C)
        from b to a through C         done clear
  D)
   from a to b through C      done clear
  View Solution play_arrow

• question_answer66)
  Heating element of an electric heater should be made with a material which should have
  A)
   high specific resistance and high melting point   done clear
  B)
   high specific resistance and low melting point done clear
  C)
   low specific resistance and low melting point done clear
  D)
   low specific resistance and high melting point done clear
  View Solution play_arrow

• question_answer67)
  A magnetic field cannot exert any force on a
  A)
   moving magnet   done clear
  B)
                     moving charge   done clear
  C)
                    stationary magnet                   done clear
  D)
   stationary charge                      done clear
  View Solution play_arrow

• question_answer68)
  Ampere rule is used to determine       
  A)
   direction of current                  done clear
  B)
   direction of magnetic field   done clear
  C)
   direction of motion of the conductor    done clear
  D)
   magnitude of current                 done clear
  View Solution play_arrow

• question_answer69)
  A magnetic field can exert force on a      
  A)
   stationary magnet                    done clear
  B)
   moving charge   done clear
  C)
                        moving magnet  done clear
  D)
                       all of these            done clear
  View Solution play_arrow

• question_answer70)
  Lines of force
  A)
   are not imaginary lines done clear
  B)
   cannot be mapped on paper done clear
  C)
   do not intersect each other   done clear
  D)
   always intersect each other done clear
  View Solution play_arrow

• question_answer71)
  Temperature of the thermocouple which is independent of the temperature of cold junction is called
  A)
   neutral temperature   done clear
  B)
   temperature of inversion done clear
  C)
   neutral temperature as well as temperature of inversion done clear
  D)
   none of these done clear
  View Solution play_arrow

• question_answer72)
  Thermoelectric current at the temperature of Inversion
  A)
   flows from copper to iron through hot junction done clear
  B)
   flows from iron to copper through hot junction   done clear
  C)
   is maximum done clear
  D)
   does not depend on the temperature of the cold junction done clear
  View Solution play_arrow

• question_answer73)
  If a line having a total resistance \[0.2\Omega \] delivers 10kW at 250 volts to a small factory, then efficiency of transmission is
  A)
   97%                         done clear
  B)
          87% done clear
  C)
   83%                       done clear
  D)
          76% done clear
  View Solution play_arrow

• question_answer74)
  An electrical heater has resistance of \[12\Omega \] and is operated from 220 volts power line. If no heat escapes from it how much time is required to raise the temperature of 40 kg of water from \[10{}^\circ C\] to \[80{}^\circ C\]?
  A)
   1456 seconds      done clear
  B)
          1828 seconds done clear
  C)
   2708 seconds        done clear
  D)
          3250 seconds done clear
  View Solution play_arrow

• question_answer75)
  The emf produced in a wire by its motion across a magnetic field does not depend upon
  A)
   length of the wire done clear
  B)
   composition of the wire   done clear
  C)
   speed of the wire done clear
  D)
   orientation of the wire done clear
  View Solution play_arrow

• question_answer76)
  If a copper ring is moved towards the north pole of a bar magnet, then
  A)
   the ring will not be affected done clear
  B)
   the ring all tend to get warm   done clear
  C)
   an alternating current will flow in the ring done clear
  D)
   the ring will be positively charged done clear
  View Solution play_arrow

• question_answer77)
  If a circular coil and a bar magnet recede from each other with the same velocity, then
  A)
   there will be no induced emf in the coil   done clear
  B)
   there will be an induced emf in the coil done clear
  C)
   an emf will be induced in the magnet done clear
  D)
  none of these done clear
  View Solution play_arrow

• question_answer78)
  A switch is always connected to the
  A)
   earth wire        done clear
  B)
          neutral wire done clear
  C)
   live wire            done clear
  D)
          none of these done clear
  View Solution play_arrow

• question_answer79)
  A fuse wire is always connected to the
  A)
   earth wire         done clear
  B)
          neutral wire done clear
  C)
   live wire            done clear
  D)
          none of these done clear
  View Solution play_arrow

• question_answer80)
  The force of repulsion between two parallel wires is \[f\] when each one of them carries a certain current\[I\]. If the current in each is doubled, the force between them would be
  A)
   \[\frac{4}{f}\]                   done clear
  B)
          \[4f\]   done clear
  C)
   \[2f\]                    done clear
  D)
          \[f\] done clear
  View Solution play_arrow

• question_answer81)
  If an electric iron draws a current of 4 A when connected to a 220 V mains, then its resistance must be
  A)
   \[1000\Omega \]            done clear
  B)
          \[44\Omega \] done clear
  C)
   \[55\Omega \]   done clear
  D)
          none of these done clear
  View Solution play_arrow

• question_answer82)
  The resistance of a conductor is reduced to half its initial value. In doing so the heating effects in the conductor will become
  A)
   half                                         done clear
  B)
   double done clear
  C)
   one-fourth        done clear
  D)
          four times done clear
  View Solution play_arrow

• question_answer83)
  The coil of a heater is cut into two equal halves and only one of them is used in the heater. Then ratio of the heat produced by this half of the coil to that produced by the original coil is
  A)
   2 : 1                         done clear
  B)
          4 : 1 done clear
  C)
   1 : 2                       done clear
  D)
          1 : 4 done clear
  View Solution play_arrow

• question_answer84)
  In electrolysis, mass of the substance liberated at cathode is proportional to
  A)
   strength of the current passed done clear
  B)
   time of passage of current done clear
  C)
   quantity of electricity passed   done clear
  D)
   none of these done clear
  View Solution play_arrow

• question_answer85)
  In an electrolyte solution, current is maintained by the flow of
  A)
   electrons only done clear
  B)
   negative ions only done clear
  C)
   positive ions only done clear
  D)
   negative and positive ions both   done clear
  View Solution play_arrow

• question_answer86)
  Conversion of heat into electrical energy may be achieved by using
  A)
   hydrometer done clear
  B)
   thermocouple   done clear
  C)
   voltmeter done clear
  D)
   photo-electric effect done clear
  View Solution play_arrow

• question_answer87)
  Heat produced in a conductor depends
  A)
   directly on time   done clear
  B)
   inversely on time done clear
  C)
   both [a] and [b] done clear
  D)
   none of these done clear
  View Solution play_arrow

• question_answer88)
  Shape of an electrolyte cell is
  A)
   flat                          done clear
  B)
   circular done clear
  C)
   cylindrical      done clear
  D)
          like an electric wire done clear
  View Solution play_arrow

• question_answer89)
  Laws of heating are given by
  A)
   Joule             done clear
  B)
                         Ohm done clear
  C)
   Maxwell          done clear
  D)
          Faraday done clear
  View Solution play_arrow

• question_answer90)
  An electric iron is based upon the principle of
  A)
   heating effect of current   done clear
  B)
   magnetic effect of current done clear
  C)
   chemical effect of current done clear
  D)
   none of these done clear
  View Solution play_arrow

• question_answer91)
  An electric bulb converts electrical energy into
  A)
   sound energy done clear
  B)
   mechanical energy done clear
  C)
   nuclear energy done clear
  D)
   none of these   done clear
  View Solution play_arrow

• question_answer92)
  Two identical heaters, each marked 1000 watt, 250 volt are placed in parallel with each other and connected to a 250 volt supply. Their combined rate of heating will be
  A)
   250W done clear
  B)
   500W done clear
  C)
   1000W done clear
  D)
   2000W   done clear
  View Solution play_arrow

• question_answer93)
  How long would it take a current to 10 amperes to put a layer of copper \[0.\text{1}\] mm thick on both sides of a rectangular plate of \[\text{1}0\text{ cm }\times \text{ 1 }\times \text{ 65}\] cm (e.c.e. of copper\[=\text{ }0\text{ }\times \text{ }000\text{33 gm}/\text{coul}\], density of Copper\[=\text{ 9 gm}/\text{cc}\])?
  A)
   9 sec done clear
  B)
   9 min done clear
  C)
   900 sec   done clear
  D)
   900 min done clear
  View Solution play_arrow

• question_answer94)
  Three equal resistors connected in series across a source of e. m. f. together dissipate 10 watt of power. What would be the power dissipated if the same resistors are connected in parallel across the same source of e. m. f?
  A)
   90 watts   done clear
  B)
   80 watts done clear
  C)
   70 watts done clear
  D)
   75 watts done clear
  View Solution play_arrow

• question_answer95)
  When the normal to a coil points in the direction of magnetic field , then flux is
  A)
   a scalar quantity   done clear
  B)
   a vector quantity done clear
  C)
   neither scalar nor vector done clear
  D)
   uncertain done clear
  View Solution play_arrow

• question_answer96)
  Lenz's law is a consequence of the law of conservation of
  A)
   energy   done clear
  B)
   momentum done clear
  C)
   angular momentum done clear
  D)
   charge and mass done clear
  View Solution play_arrow

• question_answer97)
  In a DC generator, induced emf in the armature is                      
  A)
   DC                          done clear
  B)
      AC                           done clear
  C)
      fluctuating DC done clear
  D)
   both AC and DC     done clear
  View Solution play_arrow

• question_answer98)
  The junctions of Ni-Cu thermocouple maintained at \[0{}^\circ C\] and \[100{}^\circ C\]. The Seebeck developed in the thermocouple will be  (given \[{{a}_{Ni-cu}}=16.3\times {{10}^{-6}}V{{/}^{\circ }}C\] and \[{{b}_{Ni-cu}}=-0.042\,V/{{C}^{2}}\]
  A)
  \[\text{1}.\text{42 }\times \text{ 1}{{0}^{\text{3}}}\text{ V}\]                    done clear
  B)
  \[\text{1}.\text{42 }\times \text{ 1}{{0}^{-\text{3}}}\text{ V}\]     done clear
  C)
  \[\text{14}.\text{2 }\times \text{ 1}{{0}^{\text{3}}}\text{ V}\]      done clear
  D)
         \[\text{14}.\text{2 }\times \text{ 1}{{0}^{-\text{3}}}\text{ V}\]    done clear
  View Solution play_arrow

• question_answer99)
  What is the volume of hydrogen liberated N.T.P. by the charge which liberates 0.3175gm of copper?
  A)
   224cc done clear
  B)
   112 cc   done clear
  C)
   56 cc done clear
  D)
   None of these done clear
  View Solution play_arrow

• question_answer100)
  Magnetic lines of force
  A)
   are mere directions done clear
  B)
   have no physical reality done clear
  C)
   can be used to indicate the direction of the  magnetic field at a point done clear
  D)
   all of these   done clear
  View Solution play_arrow

• question_answer101)
  Which of the following figures represents the   magnetic lines of force due to an isolated north pole?
  A)
                                                                              done clear
  B)
  done clear
  C)
                                         done clear
  D)
                 done clear
  View Solution play_arrow

• question_answer102)
  A solenoid \[\text{1}\times \text{5}\] m long and \[\text{4}\times 0\] cm in diameter (possesses 10 turn/cm. A current of \[\text{5}\times 0\] amp is flowing through it. The magnetic induction < axis inside the solenoid is
  A)
   \[2\pi \times {{10}^{-3}}\,Tesla\]                               done clear
  B)
   \[2\pi \times {{10}^{-5}}\,Tesla\] done clear
  C)
   \[4\pi \times {{10}^{-3}}\,Tesla\] done clear
  D)
   \[2\pi \times {{10}^{-5}}\,Tesla\] done clear
  View Solution play_arrow

• question_answer103)
  A coli carrying current behaves as a/an
  A)
   magnet                                 done clear
  B)
   motor done clear
  C)
   dynamo          done clear
  D)
          electric dipole done clear
  View Solution play_arrow

• question_answer104)
  Electromagnets are used in
  A)
   electric bells       done clear
  B)
          telephones done clear
  C)
   dynamos          done clear
  D)
          all of these   done clear
  View Solution play_arrow

• question_answer105)
  A carbon microscope is best used in a
  A)
   dynamo          done clear
  B)
          telephone   done clear
  C)
   transformer       done clear
  D)
          none of these done clear
  View Solution play_arrow

• question_answer106)
  When a conductor carrying an electric current is free to move in a magnetic field, the direction in which it will move in given by
  A)
   Cork-screw rule done clear
  B)
   Fleming's left hand rule   done clear
  C)
   Laplace's rule done clear
  D)
   Swimming rule done clear
  View Solution play_arrow

• question_answer107)
  In a moving coil galvanometer, deflection of the coil \[\theta \] is related to the electrical current \[i\] by the relation
  A)
   \[i\,\propto \,\tan \theta \]            done clear
  B)
          \[i\,\propto \,\theta \]   done clear
  C)
   \[i\,\propto \,{{\theta }^{2}}\]               done clear
  D)
          \[i\,\propto \,\sqrt{\theta }\] done clear
  View Solution play_arrow

• question_answer108)
  The wire having a red plastic covering is a
  A)
   live wire            done clear
  B)
          neutral wire done clear
  C)
   earth wire        done clear
  D)
          none of these done clear
  View Solution play_arrow

• question_answer109)
  The wire having a black plastic covering is a
  A)
   live wire          done clear
  B)
          neutral wire   done clear
  C)
   earth wire         done clear
  D)
          none of these done clear
  View Solution play_arrow

• question_answer110)
  The wire having a green plastic covering is a
  A)
   live wire          done clear
  B)
          neutral wire done clear
  C)
   earth wire          done clear
  D)
          none of these done clear
  View Solution play_arrow

• question_answer111)
  In order to increase the sensitivity of a moving coil galvanometer,
  A)
   the magnetic field should be increased   done clear
  B)
   the suspension wire should be made stiff done clear
  C)
   the area of the coil should be reduced done clear
  D)
   the number of turns in the coil should be reduced done clear
  View Solution play_arrow

• question_answer112)
  An ammeter should have very low resistance
  A)
   for large deflection done clear
  B)
   for better stability done clear
  C)
   so that it may not burn out done clear
  D)
   so that it may not change the value of the main current   done clear
  View Solution play_arrow

• question_answer113)
  The resistance of an ideal voltmeter is
  A)
   zero                      done clear
  B)
          infinite   done clear
  C)
   low                        done clear
  D)
          high done clear
  View Solution play_arrow

• question_answer114)
  To convert a moving coil galvanometer into an ammeter, connect
  A)
   a high resistance in series done clear
  B)
   a high resistance in parallel done clear
  C)
   a small resistance in parallel   done clear
  D)
   a small resistance in series done clear
  View Solution play_arrow

• question_answer115)
  An electric fuse works on the _____ effect of current.
  A)
   heating            done clear
  B)
          magnetic done clear
  C)
   chemical         done clear
  D)
          none of these done clear
  View Solution play_arrow

• question_answer116)
  Resistance of a conductor is reduced to half its initial value, then heating effects in the conductor will become
  A)
   half                                         done clear
  B)
   double done clear
  C)
   one-fourth        done clear
  D)
          four times done clear
  View Solution play_arrow

• question_answer117)
  The coil of a heater is cut into two equal halves and only one of them is used in the heater. The ratio of the heat produced by this half of the coil to that produced by the original coil is
  A)
   2 : 1         done clear
  B)
                          4 : 1 done clear
  C)
   1 : 2                 done clear
  D)
                          1: 4 done clear
  View Solution play_arrow

• question_answer118)
  If a charged particle moves through a magnetic field, then effect of the field is to change the particle's
  A)
   speed done clear
  B)
   energy done clear
  C)
   acceleration done clear
  D)
   direction of motion   done clear
  View Solution play_arrow

• question_answer119)
  A long straight wire carries a current 10 amp. An electron travels with a velocity \[\text{5}.0\text{ }\times \text{ 1}{{0}^{\text{6}}}\] m/sec parallel to the wire 0.1 m away from it and in a direction opposite to the current. What force does the magnetic field of current exert on the electron?
  A)
   \[0.8\times {{10}^{-17}}N\] done clear
  B)
  \[0.8\times {{10}^{-16}}N\] done clear
  C)
  \[1.6\times {{10}^{-17}}N\]   done clear
  D)
  \[1.6\times {{10}^{-16}}N\] done clear
  View Solution play_arrow

• question_answer120)
  Two straight parallel wires, both carrying 10 amperes in the same direction attract each other with a force of \[\text{1 }\times \text{ 1}{{0}^{-\text{3}}}\] N. If both currents are doubled, then force of attraction will be
  A)
  \[\text{1 }\times \text{ 1}{{0}^{-\text{3}}}\text{ N}\]         done clear
  B)
          \[\text{2 }\times \text{ 1}{{0}^{\text{-3}}}\text{ N}\] done clear
  C)
  \[~\text{4 }\times \text{ 1}{{0}^{-\text{3}}}\text{ N}\]           done clear
  D)
          \[0.\text{25 }\times \text{ 1}{{0}^{-\text{3}}}\text{ N}\] done clear
  View Solution play_arrow

• question_answer121)
  Electrical switches are put in the
  A)
   live wire                done clear
  B)
   earth wire done clear
  C)
   neutral wire                      done clear
  D)
   none of these done clear
  View Solution play_arrow

• question_answer122)
  Various distribution circuits are connected in
  A)
   series done clear
  B)
   parallel   done clear
  C)
   series or parallel done clear
  D)
   nothing can be decided done clear
  View Solution play_arrow

• question_answer123)
  If a fuse wire is generally made of
  A)
   tin done clear
  B)
   tin-lead alloy done clear
  C)
   copper done clear
  D)
   either [a] or [b] above   done clear
  View Solution play_arrow

• question_answer124)
  If two infinitely long wires carry currents in the same direction, then the field at a point P which is lying midway between them is
  A)
   twice the field due to each of the wires done clear
  B)
   half of the field due to each wire alone done clear
  C)
   square of the field due to each wire alone done clear
  D)
   zero   done clear
  View Solution play_arrow

• question_answer125)
  A motor converts
  A)
   mechanical energy into electrical energy done clear
  B)
   mechanical energy into sound energy done clear
  C)
   electrical energy into mechanical energy   done clear
  D)
   electrical energy into sound energy done clear
  View Solution play_arrow

• question_answer126)
  A dynamo converts
  A)
   mechanical energy into sound energy done clear
  B)
   mechanical energy into electrical energy   done clear
  C)
   electrical energy into mechanical energy done clear
  D)
   electrical energy into sound energy done clear
  View Solution play_arrow

• question_answer127)
  By inserting a soft iron piece into a solenoid, strength of the magnetic field
  A)
   increases   done clear
  B)
   decreases done clear
  C)
   first increases then decreases done clear
  D)
   remains unchanged done clear
  View Solution play_arrow

• question_answer128)
  An electric charge does not experience a force due to a magnetic field,
  A)
   is stationary done clear
  B)
   moves parallel to the magnetic field done clear
  C)
   both [a] and [b] above   done clear
  D)
   moves perpendicular to the field done clear
  View Solution play_arrow

• question_answer129)
  When the radius of the circular current carrying coil is doubled and the current in it is Halved then magnetic dipole moment of the coil originally four units becomes               
  A)
   4 units                  done clear
  B)
                8 units                    done clear
  C)
                16 units                             done clear
  D)
   32 units                      done clear
  View Solution play_arrow

• question_answer130)
          By increasing the number of turns in the coil the strength of the magnetic field
  A)
   decreases            done clear
  B)
                  increases   done clear
  C)
   first decreases then increases           done clear
  D)
   remains unchanged done clear
  View Solution play_arrow

• question_answer131)
  If current in the core decreases, then strength of the magnetic field
  A)
   decreases   done clear
  B)
   increases done clear
  C)
   sometimes decreases and sometimes increases done clear
  D)
   remains unchanged done clear
  View Solution play_arrow

• question_answer132)
  Resistance of a galvanometer coil is 600 ohms and a shunt is put in parallel to it. If only 1% of the main current passes through the galvanometer, then multiplying factor K is
  A)
   10 done clear
  B)
   100   done clear
  C)
   600 done clear
  D)
   60 done clear
  View Solution play_arrow

• question_answer133)
  Two particles X and Y having equal charges, after being accelerated through the same potential difference, enter a region of uniform magnetic field and describe circular paths or radii \[{{R}_{1}}\] and \[{{R}_{2}}\] respectively. The ratio of mass of X to that of Y is equal to
  A)
   \[{{\left( \frac{{{R}_{1}}}{{{R}_{2}}} \right)}^{2}}\]             done clear
  B)
          \[\left( \frac{{{R}_{1}}}{{{R}_{2}}} \right)\] done clear
  C)
   \[{{\left( \frac{{{R}_{1}}}{{{R}_{2}}} \right)}^{\frac{1}{2}}}\]         done clear
  D)
          \[\frac{{{R}_{2}}}{{{R}_{1}}}\] done clear
  View Solution play_arrow

• question_answer134)
  A proton of a mass m and charge +e is moving in magnetic field with energy 1 MeV. should be the energy of \[\alpha \]-particle (mass \[4m\] and charge\[+2e\]) so that it can revolve in the path of same radius?
  A)
   \[1\,\,MeV\]       done clear
  B)
          \[4\,\,MeV\] done clear
  C)
   \[2\,\,MeV\]     done clear
  D)
          \[0.5\,\,MeV\] done clear
  View Solution play_arrow

• question_answer135)
  The unit of magnetic flux is
  A)
   Weber   done clear
  B)
   Gauss done clear
  C)
   Tesla done clear
  D)
   \[\text{Weber}/{{\text{m}}^{\text{2}}}\] done clear
  View Solution play_arrow

• question_answer136)
  Fleming's right hand rule gives
  A)
   magnitude of the induced emf done clear
  B)
   magnitude of the magnetic field done clear
  C)
   direction of the induced emf   done clear
  D)
   both magnitude and direction of the induced emf done clear
  View Solution play_arrow

• question_answer137)
  Unit of induced emf is
  A)
   ampere done clear
  B)
   volt   done clear
  C)
   joule done clear
  D)
   electron volt done clear
  View Solution play_arrow

• question_answer138)
  There will be no force between two wires carrying currents if currents are
  A)
   parallel to each other done clear
  B)
   antiparallel to each other done clear
  C)
   perpendicular to each other   done clear
  D)
   none of these done clear
  View Solution play_arrow

• question_answer139)
  A long current carrying wire PQ is free to move when placed in a magnetic field B at right angles to the wire, as shown (the figure being drawn in the horizontal plane). Then it will
  A)
   move along the magnetic field to the right done clear
  B)
   move upwards, towards the observer   done clear
  C)
   move downwards, away from the observer done clear
  D)
   not move at all done clear
  View Solution play_arrow

• question_answer140)
  Through a metallic conductor electric current is thought to be a movement of
  A)
   Ions done clear
  B)
   Amperes done clear
  C)
   Electrons   done clear
  D)
   Protons done clear
  View Solution play_arrow

• question_answer141)
  10,000 alpha particles per minute are passing through a straight tube of radius r. The resulting electric current is approximately
  A)
  \[0.5\times {{10}^{-16}}A\]         done clear
  B)
          \[2\times {{10}^{12}}A\] done clear
  C)
  \[0.5\times {{10}^{12}}A\]      done clear
  D)
          \[2\times {{10}^{-12}}A\] done clear
  View Solution play_arrow

• question_answer142)
  The ampere-sec stands for the unit of
  A)
   Power                  done clear
  B)
          Current done clear
  C)
   Energy                 done clear
  D)
          Charge   done clear
  View Solution play_arrow

• question_answer143)
  An electric iron draws 10 amp, an electric toaster draws 5 amp and an electric refrigerator draws 3 amp from and 220 volts service line. The three appliances are connected in parallel. If all the three are operating at the same time, the fuse to be used should be of
  A)
   10 amp          done clear
  B)
          5 amp done clear
  C)
   15 amp                                done clear
  D)
   20 amp   done clear
  View Solution play_arrow

• question_answer144)
  Electric current is due to drift of electrons in
  A)
   Metallic conductors   done clear
  B)
   Semiconductors done clear
  C)
   Both [a] and [b] above done clear
  D)
   None of the above done clear
  View Solution play_arrow

• question_answer145)
  The resistance of a wire of uniform diameter D and length L is R. The resistance of another wire of the same material but diameter 2 D and length 4 L will be
  A)
   \[2R\]                  done clear
  B)
          \[R,\]   done clear
  C)
   \[\frac{R}{2}\]                  done clear
  D)
          \[\frac{R}{4}\] done clear
  View Solution play_arrow

• question_answer146)
  If on stretching wire its radius decreases by 1%, the resistance will
  A)
   increase by 1% done clear
  B)
   increase by 2% done clear
  C)
   increase by 4%   done clear
  D)
   not change done clear
  View Solution play_arrow

• question_answer147)
  The resistance R of a conductor varies with temperature as shown in the given figure. If it is written as, \[{{R}_{t}}={{R}_{0}}(1+t+{{t}^{2}})\]
  A)
   a and P are both negative                done clear
  B)
   a is positive but P is negative T      done clear
  C)
   a and P are both positive          done clear
  D)
   a is negative but P is positive        done clear
  View Solution play_arrow

• question_answer148)
  A resistance of 0.01 ohms is connected in parallel with a resistance of one kilo ohm. The resistance of the combination will be
  A)
   1000 \[ohm\] done clear
  B)
   10 \[ohm\] done clear
  C)
   1 \[ohm\] done clear
  D)
   0.01 \[ohm\]   done clear
  View Solution play_arrow

• question_answer149)
  Given three equal resistors. How many different combination of these three resistances can be made?
  A)
   Six done clear
  B)
   Five done clear
  C)
   Four   done clear
  D)
   Three done clear
  View Solution play_arrow

• question_answer150)
  In the given circuit, each resistance is\[10\text{ }\Omega \]. The equivalent resistance between A and D is
  A)
  \[\text{4}0\text{ }\Omega \]         done clear
  B)
  \[30\text{ }\Omega \]             done clear
  C)
   \[20\text{ }\Omega \]          done clear
  D)
   \[10\text{ }\Omega \]        done clear
  View Solution play_arrow

• question_answer151)
  The effective resistance between the terminals A and B is equal to
  A)
   25 ohms             done clear
  B)
   25 ohms          done clear
  C)
   10 ohms   done clear
  D)
   5 ohms             done clear
  View Solution play_arrow

• question_answer152)
  All the resistance in the figure are in ohms. The effective resistance between points A and B is
  A)
   6 ohms         done clear
  B)
   3 ohms      done clear
  C)
   9 ohms    done clear
  D)
   2 ohms           done clear
  View Solution play_arrow

• question_answer153)
  In a Wheatstone bridge shown in figure \[(x=y)\] and A > B. The direction of the current between a and b will be
  A)
    From a to b   done clear
  B)
   From b to a      done clear
  C)
   from a to b through c  done clear
  D)
    from b to a through c done clear
  View Solution play_arrow

• question_answer154)
  You have the following appliances each of 500 watts, running on 220 volts A.C (i) electric iron (ii) an electric lamp (iii) an electric room heater The electrical resistance is:
  A)
   maximum for the room heater         done clear
  B)
   maximum for the electric lamp done clear
  C)
   maximum for electric iron done clear
  D)
   same in all the three cases   done clear
  View Solution play_arrow

• question_answer155)
  An electric bulb rated 200 V and 100 W is connected to a 160 V power supply. The power consumption would be
  A)
   64 W                                       done clear
  B)
   80 W done clear
  C)
   100 W                   done clear
  D)
          125 W done clear
  View Solution play_arrow

• question_answer156)
  In the circuit shown in the figure, \[{{R}_{1}}>{{R}_{2}}.\]in which resistance the power dissipated is greater
  A)
   In \[{{R}_{1}}\]                 done clear
  B)
   In \[{{R}_{2}}\]   done clear
  C)
   Equal in both done clear
  D)
          Uncertain done clear
  View Solution play_arrow

• question_answer157)
  Four bulbs marked 40 W, 250 V are connected in series with 250 V mains, the total power consumed is
  A)
   10 W   done clear
  B)
   40 W done clear
  C)
   320 W done clear
  D)
   160 W done clear
  View Solution play_arrow

• question_answer158)
  Ten identical electric bulbs, each rated 220 V, 50 W are used in parallel on 220 V line for 10 hours per day in a month of 30 days. The electric energy consumed in kilo watt hours is
  A)
   1500 done clear
  B)
   15,000 done clear
  C)
   15 done clear
  D)
   150   done clear
  View Solution play_arrow

• question_answer159)
  A cell emf E is connected across a resistance R. The potential difference between the terminals of the cell is found to be V. The internal resistance of the cell must be
  A)
   \[\frac{2(E-V)V}{R}\]     done clear
  B)
          \[\frac{2(E-V)R}{E}\] done clear
  C)
   \[\frac{(E-V)R}{V}\]         done clear
  D)
          \[(E-V)R\] done clear
  View Solution play_arrow

• question_answer160)
  A battery of emf 2 volt and internal resistance \[0.1\]ohm is being charged with a current of 5 ampere. The potential difference between the two terminals of the batteries is
  A)
   \[2V\]                  done clear
  B)
          \[0.5\,V\] done clear
  C)
   \[1.5\,V\]                           done clear
  D)
          \[2.5\,V\]   done clear
  View Solution play_arrow

• question_answer161)
  An external resistance R is connected to a cell of internal resistance r. The largest amount of current flows in the external resistance, when
  A)
   \[R<r\]                                 done clear
  B)
   \[R>r\] done clear
  C)
   \[R=r\]             done clear
  D)
                          Any other value of R   done clear
  View Solution play_arrow

• question_answer162)
  Two cells of same emf E but different internal resistances \[{{r}_{1}}\] and \[{{r}_{2}}\] are connected in series with an external resistance R. The potential drop across the first cell is found to be zero. The external resistance R is
  A)
   \[{{r}_{1}}+{{r}_{2}}\]           done clear
  B)
        \[{{r}_{1}}-{{r}_{2}}\]   done clear
  C)
   \[{{r}_{2}}-{{r}_{1}}\]            done clear
  D)
        \[{{r}_{1}}{{r}_{2}}\] done clear
  View Solution play_arrow

• question_answer163)
  A cell of negligible resistance and emf 2 volt is connected to series combination of 2,3 and 5 ohm. The potential difference in volts between the terminals of 3 ohm resistance will be
  A)
   \[0.\text{6}\]ohm                             done clear
  B)
   \[2/3\]volt done clear
  C)
   3 volts            done clear
  D)
          6 volts done clear
  View Solution play_arrow

• question_answer164)
  The current flowing through 3 ohm resistor is 0.8 ampere, the potential drop across the 4 ohm resistor is                  
  A)
   \[1.6\,\,V\]                        done clear
  B)
   \[2.4\,\,V\] done clear
  C)
   \[4.8\,\,V\]          done clear
  D)
          \[9.6\,\,V\] done clear
  View Solution play_arrow

• question_answer165)
  In the circuit shown in figure, what will be the reading of the ammeter?
  A)
   \[0.36\,ampere\]            done clear
  B)
          \[0.50\,ampere\]   done clear
  C)
   \[2.0\,ampere\]              done clear
  D)
          \[4.5\,ampere\] done clear
  View Solution play_arrow

• question_answer166)
  How will the reading in the ammeter of figure be affected if another identical bulb \[Q\] is connected in parallel to \[P\] as shown. If the voltage in the mains is maintained at a constant value,
  A)
   the reading will be reduced to one half done clear
  B)
   the reading will not be affected done clear
  C)
   the reading will be doubled of the previous value   done clear
  D)
   the reading will be increased four fold done clear
  View Solution play_arrow

• question_answer167)
  Seven identical lamps of resistance 2200 ohms each are connected to 220 volts line as shown in the figure. What will be the reading in the ammeter?
  A)
    \[\frac{1}{10}\] ampere              done clear
  B)
   \[\frac{3}{10}\] ampere done clear
  C)
   \[\frac{4}{10}\]ampere       done clear
  D)
          None of these   done clear
  View Solution play_arrow

• question_answer168)
  Four identical resistors of 4 ohm each are joined in circuit as shown in the figure. The cell B has emf 2 volts and its internal resistance is negligible. The ammeter will read
  A)
    \[\frac{3}{8}\] ampere         done clear
  B)
          2 ampere done clear
  C)
   \[\frac{1}{2}\] ampere       done clear
  D)
          \[\frac{1}{8}\] ampere done clear
  View Solution play_arrow

• question_answer169)
  Voltmeters \[{{V}_{1}}\] and \[{{V}_{2}}\] are connected in series across a D.C. line. \[{{V}_{1}}\] reads 80 V and has a per volt resistance of \[200\Omega \],  \[{{V}_{2}}\]has a total resistance of\[32\Omega \]. The line voltage is
  A)
   \[120V\]                              done clear
  B)
   \[160\,V\] done clear
  C)
   \[220\,V\]            done clear
  D)
          \[240\,V\]   done clear
  View Solution play_arrow

• question_answer170)
  The resistance \[500\Omega \] and \[1000\Omega \] are connected in series with battery of \[1.5\] volts. The voltage across the 100 ohm resistance is measured by a voltmeter having a resistance of 1000 ohm. The reading in voltmeter would be
  A)
  \[\text{1}\text{.5 volt}\]          done clear
  B)
          \[\text{1}.0\text{ volt}\] done clear
  C)
  \[0.\text{75 volt}\]                done clear
  D)
          \[0.\text{5 volt}\] done clear
  View Solution play_arrow

• question_answer171)
  In the circuit shown in figure, the voltmeter reading would be
  A)
   \[0\] volt                               done clear
  B)
   \[0.5\]volt done clear
  C)
   1 volt                    done clear
  D)
   2 volt done clear
  View Solution play_arrow

• question_answer172)
  The arm PQ can revolve with uniform speed continuously about P round the circular uniform potentiometer track\[X-Y-Z\]. The voltage between RS will vary with respect to time
  A)
   Sinusoid ally     done clear
  B)
          Linearly done clear
  C)
   Rectangular done clear
  D)
          Like saw tooth   done clear
  View Solution play_arrow

• question_answer173)
  A battery of 6 V is connected to the terminals of three metre long wire of uniform thickness and resistance of the order of 100 ohms. The difference of potential between two points separated by 50 cm on the wire will be
  A)
   1 volt                 done clear
  B)
          \[\text{1}\text{.5}\]volts done clear
  C)
   2 volts              done clear
  D)
          3 volts done clear
  View Solution play_arrow

• question_answer174)
  There is a fixed potential difference between the two ends of a potentiometer. Two cells are connected in series in such a way that in one arrangement they help each other where as in the second arrangement they oppose each other The balance point for these two combinations is obtained at 120 cm and 60 cm length respectively. The ratio of the emf of the cell is        
  A)
   2 : 1             done clear
  B)
                         3:1           done clear
  C)
   1:1                         done clear
  D)
          4:1            done clear
  View Solution play_arrow

• question_answer175)
  The electric current passing through a metallic wire produces heating because of
  A)
   collisions of conduction electrons with each other done clear
  B)
   collisions of the atoms of the metal with each other done clear
  C)
   the energy released in the ionization  of the atoms of the metal done clear
  D)
   collisions of the conduction electrons with the  atoms of the metallic wire   done clear
  View Solution play_arrow

• question_answer176)
  In the circuit shown in Figure the heat produce! in resistance \[{{R}_{1}}\] can be measured by
  A)
   connecting both voltmeter and an ammeter min parallel to \[{{R}_{1}}\] done clear
  B)
   connecting both voltmeter in series with \[{{R}_{1}}\]and voltmeter in parallel to both \[{{R}_{1}}\]and \[{{R}_{2}}\] done clear
  C)
   connecting ammeter in parallel to \[{{R}_{1}}\] and voltmeter in series with \[{{R}_{1}}\] done clear
  D)
   connecting voltmeter in parallel to \[{{R}_{1}}\] and ammeter in series with \[{{R}_{1}}\]   done clear
  View Solution play_arrow

• question_answer177)
  An electric heater has resistance 150 ohms and can bear a maximum current of 1 ampere. If the heater is to be used on 220 volt mains, the least resistance required in the circuit will be
  A)
   70 ohms                done clear
  B)
   5 ohms done clear
  C)
   \[2.5\] ohms         done clear
  D)
          \[1.4\] ohms done clear
  View Solution play_arrow

• question_answer178)
  If the current is flowing through a 10 ohm resistor then indicate in which case the maximum heat will be generated?
  A)
   5 ampere in 2 minutes done clear
  B)
   4 ampere in 3 minutes done clear
  C)
   3 ampere in 6 minutes   done clear
  D)
   2 ampere in 5 minutes done clear
  View Solution play_arrow

• question_answer179)
  A heater of 220 V boils a volume of water in 5 mninute time. If the heater is operated at 110 V, the same volume of water will boil in
  A)
   5 min                    done clear
  B)
          8 mm done clear
  C)
   10 min                                  done clear
  D)
   20 min   done clear
  View Solution play_arrow

• question_answer180)
  resistors of 6 ohm and 9 ohm are connected in series to a 120 V source. The power consumed by the 6 ohm resistor is
  A)
   384W   done clear
  B)
   576 W done clear
  C)
   1500W done clear
  D)
   1800W done clear
  View Solution play_arrow

• question_answer181)
  You are given a resistance wire of length 50 cm and a battery of negligible resistance. In which of the following cases is largest amount of heat generated
  A)
   When the wire is connected to the battery directly done clear
  B)
   When the wire is divided in two equal parts and both the parts are connected to the battery in parallel. done clear
  C)
   When the wire is divided in four equal parts and all four parts are connected to the battery in parallel.   done clear
  D)
   When only half the wire is connected to the battery done clear
  View Solution play_arrow

• question_answer182)
  In the circuit shown in the figure, the heat produced in the 5 ohm resistor due to the current flowing through it is 10 calories per second. The heat generated in the 4 ohm resistor is
  A)
   1 calorie/sec  done clear
  B)
   2 calories/sec   done clear
  C)
   3 calories/sec done clear
  D)
   4 calories/sec done clear
  View Solution play_arrow

• question_answer183)
  Two electric bulbs one of 200 volts and 40 watts and the other 200 volts and 100 watts are connected in a house wiring circuit
  A)
   They have equal current through them done clear
  B)
   The resistance of the filaments of both the bulbs is same done clear
  C)
   The resistance of the filament of 40 W bulb is more than that of 100 watt bulb   done clear
  D)
   The resistance of 100 watt bulb is more than 40 watt bulb done clear
  View Solution play_arrow

• question_answer184)
  A 200 W and a 100 W bulbs, both meant for operation at 220 V, are connected in series, to a 220 V supply. The power consumed by them will be
  A)
   33 W          done clear
  B)
   66 W   done clear
  C)
   100 W done clear
  D)
   300 W done clear
  View Solution play_arrow

• question_answer185)
  Three bulbs \[{{B}_{1}},{{B}_{2}}\] and \[{{B}_{3}}\] are connected to the mains as shown in the figure. How will the incandesence of the bulb  \[{{B}_{1}}\]be affected, if one of the bulb \[{{B}_{2}}\]or \[{{B}_{3}}\] is disconnected from the circuit
  A)
   No change in the incandescence done clear
  B)
   Bulb \[{{B}_{1}}\] will become brighter done clear
  C)
   The bulb \[{{B}_{1}}\] will become less brighter   done clear
  D)
   The bulb \[{{B}_{1}}\] may become brighter or dimmer depending upon the candle power of the bulb which is disconnected done clear
  View Solution play_arrow

• question_answer186)
  Why do, the light of a car dim when the strater is operated?
  A)
   The strater motor draws a larger current resulting in a larger potential drop in the battery which reduces the terminal voltage of the battery   done clear
  B)
   When the strater motor is switched on, it increases the resistance of the filament of the bulb in the car light done clear
  C)
   When the strater motor is switched on \[j\] reduces the EMF of the battery done clear
  D)
   none of these done clear
  View Solution play_arrow

• question_answer187)
  Molten sodium-chloride conducts electricit to the presence of
  A)
   Free electrons done clear
  B)
   Free ions   done clear
  C)
   Free molecules done clear
  D)
   Free atoms of Na and CI done clear
  View Solution play_arrow

• question_answer188)
  Direct current is passed through copper sulphate solution using platinum electrodes. The elements liberated at the electrodes are
  A)
   copper at anode and sulphate at cathode done clear
  B)
   sulphur at anode and copper at cathode done clear
  C)
   oxygen at anode and copper at cathode   done clear
  D)
   copper at anode and oxygen at cathode done clear
  View Solution play_arrow

• question_answer189)
  The internal resistance of a primary cell is 4 ohm. It generates a current of 0.2 ampere in an external resistance of 2 ohm. The rate at which chemical energy is consumed in providing the current is
  A)
   \[0.42\,J\text{/}s\]             done clear
  B)
          \[0.24\,J\text{/}s\]   done clear
  C)
   \[5\,J\text{/}s\]                 done clear
  D)
          \[1\,J\text{/}s\] done clear
  View Solution play_arrow

• question_answer190)
  In a copper voltmeter containing copper sulphate solution, a current of 1 ampere is passed for 1 hours. Taking the E.C.E. of copper as \[0.000\text{329}\] g/coul, the weight of copper deposited is approximately
  A)
   \[0.6\] gm            done clear
  B)
          \[1.2\]gm   done clear
  C)
   \[0.12\,\,gm\]           done clear
  D)
          \[0.0\text{329 gm}\] done clear
  View Solution play_arrow

• question_answer191)
  When the same amount of charge is passed through the solution of different electrolytes, the amounts of elements deposited on the electrodes are in the ratio of their
  A)
   Atomic number  done clear
  B)
         Atomic weights done clear
  C)
   Specific gravities done clear
  D)
         Equivalent weights   done clear
  View Solution play_arrow

• question_answer192)
  In an electrolysis experiment a current C passes through two different cells in series, one containing a solution of copper sulphate and the other a solution of silver nitrate. The ratio of increase of the weights at cathode in the two cells will be
  A)
   in the ratio of the atomic weights of copper and silver done clear
  B)
   in the ratio of the density of copper and silver done clear
  C)
   in the ratio of half the atomic weight of copper to the atomic weight of silver   done clear
  D)
   in the ratio of half the atomic weight of copper to half the atomic weight of silver done clear
  View Solution play_arrow

• question_answer193)
  Which of the following is a universal constant?
  A)
   Farad done clear
  B)
   Chemical equivalent (CE) done clear
  C)
   Electrochemical equivalent (ECE) done clear
  D)
   Faraday   done clear
  View Solution play_arrow

• question_answer194)
  The commercial aluminium (trivalent : atomic weight 27) is generally obtained by electrolysis of \[AlC{{l}_{3}}\]. The charge required to deposit \[\text{13}\text{.5}\] gm of aluminium is
  A)
   \[0.5\,\,F\]                 done clear
  B)
          \[1.0\,\,F\] done clear
  C)
   \[1.5\,\,F\]                   done clear
  D)
          \[2.0\,\,F\] done clear
  View Solution play_arrow

• question_answer195)
  96,000 coulombs deposit on gm atom of monovalent silver. The positive charge on a silver ion is equal in magnitude to that of an electron and Avogadro's number is\[\text{6 }\times \text{ 1}{{0}^{\text{23}}}\]. Electronic charge will be                          
  A)
   \[-1.6\times {{10}^{-19}}\text{coulomb}\]   done clear
  B)
  \[5.76\times {{10}^{28}}\text{coulomb}\] done clear
  C)
   \[6.2\times {{10}^{18}}\text{coulomb}\] done clear
  D)
   \[\text{-160}\,\,\text{coulomb}\] done clear
  View Solution play_arrow

• question_answer196)
  In electroplating, the article to be electroplated serves as
  A)
   Cathode                 done clear
  B)
                  Anode                  done clear
  C)
                Electrolyte           done clear
  D)
                Conductor                 done clear
  View Solution play_arrow

• question_answer197)
          The graph represents a current-voltage behavior of a water-voltmeter. Spot the correct explanation.
  A)
   Dissociation takes place and it obeys Ohm's law thereafter done clear
  B)
   Ohm's law is not valid for low voltage done clear
  C)
   Ohm's law is obeyed but only for potential   done clear
  D)
   Electrolytes do not obey Ohm's law done clear
  View Solution play_arrow

• question_answer198)
  If the radius of a copper wire carrying a current is doubled, the drift velocity of the electrons will
  A)
   remain same done clear
  B)
   increase four times done clear
  C)
   decrease four times   done clear
  D)
   increase first and then will decrease done clear
  View Solution play_arrow

• question_answer199)
  In the given figure, a fuse in one of the bulbs causes all the others to go out. Which bulb has fused ?
  A)
   1                               done clear
  B)
   4 done clear
  C)
   3                        done clear
  D)
          2 done clear
  View Solution play_arrow

• question_answer200)
  Is it possible that any battery has some constant value of emf but the potential difference between the plates is zero?
  A)
   Not possible done clear
  B)
   Yes, if another identical battery is joined is series                                         done clear
  C)
   Yes, possible if another battery is joined in opposition done clear
  D)
   Yes, possible if another similar battery is joined in parallel done clear
  View Solution play_arrow

• question_answer201)
  If we  impurity to a metal, those atoms also deflect electrons. Therefore,
  A)
   the electrical and thermal conductivity both increases done clear
  B)
   the electrical and thermal conductivity both decreases   done clear
  C)
   electrical conductivity increase but thermal conductivity decreases done clear
  D)
   thermal conductivity increases but electrical conductivity decreases done clear
  View Solution play_arrow

• question_answer202)
  A cell of emf E volts with no internal resistance is connected to a wire of uneven cross-sectional area. The wire has three sections of equal length. The radius of the middle section is a and the other are 2 a. The ratio of the potential difference across the middle section to any other section is
  A)
   2 :1                                        done clear
  B)
   4 : 1   done clear
  C)
   1:2                         done clear
  D)
          1 : 4 done clear
  View Solution play_arrow

• question_answer203)
  A current of 2 A flows in a system of conductors as shown in the figure. The potential difference\[{{V}_{A}}-{{V}_{B}}\]is
  A)
   \[+\,2\,V\]                           done clear
  B)
   \[+\,1\,V\] done clear
  C)
   \[-\,1\,V\]          done clear
  D)
          \[-\,2\,V\] done clear
  View Solution play_arrow

• question_answer204)
  In the network given below, the current flowing through the resistance 2 R, is
  A)
   \[\frac{E}{R}\]                                  done clear
  B)
   \[\frac{E}{7R}\] done clear
  C)
   \[\frac{2E}{7R}\]                                done clear
  D)
          \[\frac{2E}{R}\] done clear
  View Solution play_arrow

• question_answer205)
  A cell supplies a current of \[0.9\] A through a \[2\Omega \] resistor and \[0.3\] A through a \[7\Omega \] resistor. What is the internal resistance of the cell?
  A)
   \[0.5\,\,\Omega \]                   done clear
  B)
          \[1\,\,\Omega \] done clear
  C)
   \[1.2\,\,\Omega \]                 done clear
  D)
          \[2\,\,\Omega \] done clear
  View Solution play_arrow

• question_answer206)
  A uniform wire of length 5 cm is carrying a steady current. The electric field inside it is\[0.\text{2 V}/\text{m}\]. The potential difference across the ends of the wire is
  A)
   \[0.1\,V\]               done clear
  B)
          \[0.5\,V\] done clear
  C)
   \[5\,V\]                               done clear
  D)
          \[{{10}^{-2}}\,V\]   done clear
  View Solution play_arrow

• question_answer207)
  Which one of the following is the best material for making connecting wires?
  A)
   Nichrome           done clear
  B)
   Constantan done clear
  C)
   Copper           done clear
  D)
          Tungsten   done clear
  View Solution play_arrow

• question_answer208)
  The circuit shown in figure was set up to determine the emf of a thermo cell. As P is moved away from X to Y, the galvanometer deflection is always in the same direction but decrease continuously until Y is reached. In order to obtain a balance point between X and Y, it is necessary to
  A)
   decreases R   done clear
  B)
   increases R done clear
  C)
   reverse the terminals of E done clear
  D)
   interchange the hot and cold junctions done clear
  View Solution play_arrow

• question_answer209)
  In order to balance the Whetstone bridge as shown in the figure, a 100 ohm resistor is to be connected in parallel to one of the existing arms. In which arm of the bridge must the resistor be connected ?
  A)
   PQ                                         done clear
  B)
   QR   done clear
  C)
   PS                          done clear
  D)
          RS done clear
  View Solution play_arrow

• question_answer210)
  A voltmeter reading upto 100 mV is calibrated by a potentiometer. An emf of \[\text{1}.0\text{8}\] V is balanced across \[\text{5}\text{.4}\] m length of the wire. When voltmeter reading is \[0.\text{9}\] V, the balancing length is \[\text{4}\text{.55}\] m. The error in the voltmeter reading is
  A)
  \[-0.01\,V\]                          done clear
  B)
   \[-0.1\,V\] done clear
  C)
   \[-0.001\,V\]           done clear
  D)
          \[0\,V\] done clear
  View Solution play_arrow

• question_answer211)
  A potentiometer has a driving cell of negligible internal resistance. The balancing length of a Daniel cell is 5 m. If the driving cell had internal resistance, the balancing length of the same Daniel cell would have been
  A)
   more   done clear
  B)
   less done clear
  C)
   same done clear
  D)
   cannot be said from the data done clear
  View Solution play_arrow

• question_answer212)
  In the equation AB = C, where A is current density, C is electric field. Then B is
  A)
   resistivity   done clear
  B)
   conductivity done clear
  C)
   potential difference done clear
  D)
   resistance done clear
  View Solution play_arrow

• question_answer213)
  In a meter bridge, a standard resistor of R ohm is connected in the left gap and two wires A and B are connected one after the other in the right gap. The balancing length measured from the left is 50 cm for either of them. If the two wires are connected is series and put in the right gap, the balancing length measured from the left would be (in cm)
  A)
   25   done clear
  B)
  \[~\text{33}\text{.3}\] done clear
  C)
   \[\text{66}\text{.7}\] done clear
  D)
   75 done clear
  View Solution play_arrow

• question_answer214)
  Two bulbs of 100 W and 40 W are connected in series. The current through the 100 W bulb is 1 The current through the 40 W bulb will be
  A)
   \[0.4\,\,A\]                        done clear
  B)
   \[0.6\,\,A\] done clear
  C)
   \[0.8\,\,A\]                 done clear
  D)
          \[1\,\,A\]   done clear
  View Solution play_arrow

• question_answer215)
  Seven resistors, each of value \[5\Omega \] are connected as shown in figure. The equivalent resistance between points A and B is
  A)
   \[5\Omega \]                    done clear
  B)
   \[7\Omega \]   done clear
  C)
   \[14\Omega \]               done clear
  D)
          \[35\Omega \] done clear
  View Solution play_arrow

• question_answer216)
  The resistance between points A and B the circuit shown in figure is              
  A)
   \[4\Omega \]                    done clear
  B)
          \[6\Omega \] done clear
  C)
   \[10\,\Omega \]                done clear
  D)
          \[8\,\Omega \] done clear
  View Solution play_arrow

• question_answer217)
  Figure shows a circuit with two cells in opposition to each other. One cell has an emf of 6 V and internal resistance of \[2\,\Omega \] and the other cell has an emf of 4 V and internal resistance of \[8\,\Omega \]. The potential difference across the terminal X and Y is
  A)
   \[5.4\,\,V\]        done clear
  B)
          \[5.6\,\,V\] done clear
  C)
   \[5.8\,\,V\]        done clear
  D)
          \[6.0\,\,V\]   done clear
  View Solution play_arrow

• question_answer218)
  The unit of specific conductance is
  A)
   ohm                      done clear
  B)
          ohm-metre done clear
  C)
   siemen                done clear
  D)
          siemen per metre   done clear
  View Solution play_arrow

• question_answer219)
  In the given circuit below, which switch, when closed, will produce short-circuiting?
  A)
   1                               done clear
  B)
          2 done clear
  C)
   3                             done clear
  D)
          2 and 3 done clear
  View Solution play_arrow

• question_answer220)
  A student connects four 1/4 ohm cells in series but one cell has its terminals reversed. If each cell has an emf of \[1.5\] V and the external resistance is \[\text{2}\Omega \] , then the current flowing is
  A)
   \[1\,\,A\]                              done clear
  B)
          \[1.5\,\,A\] done clear
  C)
   \[2.5\,\,A\]             done clear
  D)
          zero done clear
  View Solution play_arrow

• question_answer221)
  In the network shown below, the equivalent resistance between P and \[Q\] is \[\frac{4}{3}Q\]. Hence the value of r is
  A)
   \[3\,\,\Omega \]                                             done clear
  B)
   \[4\,\,\Omega \] done clear
  C)
   \[5\,\,\Omega \]                             done clear
  D)
          \[6\,\,\Omega \]   done clear
  View Solution play_arrow

• question_answer222)
  The resistivity of a wire varies with its
  A)
   length            done clear
  B)
          cross-section done clear
  C)
   mass                     done clear
  D)
          material   done clear
  View Solution play_arrow

• question_answer223)
  The resistance of a straight conductor does not depend on its
  A)
   temperature done clear
  B)
   length done clear
  C)
   material done clear
  D)
   shape of cross-section   done clear
  View Solution play_arrow

• question_answer224)
  e. m. f. is measured in
  A)
   joules done clear
  B)
   joules/coulomb   done clear
  C)
   joule-coulombs done clear
  D)
   joule/coulomb done clear
  View Solution play_arrow

• question_answer225)
  1 kilowatt hour is commonly known as
  A)
   1 unit   done clear
  B)
   1 faraday done clear
  C)
   1 curie done clear
  D)
   none of these done clear
  View Solution play_arrow

• question_answer226)
  Faraday's constant, F equals
  A)
   96,5000 done clear
  B)
   \[\text{96},\text{5}000\text{k}{{\text{g}}^{-\text{1}}}\] done clear
  C)
   \[\text{96},\text{5}00\text{ kg }{{\text{C}}^{-\text{1}}}\] done clear
  D)
   \[\text{96},\text{5}00\text{ C mo}{{\text{l}}^{-\text{1}}}\]   done clear
  View Solution play_arrow

• question_answer227)
  What is the minimum number of bulbs, each marked 60 W, 40 V, that can work safely when connected in series with a 240 V mains supply?
  A)
   2 done clear
  B)
   4 done clear
  C)
   6   done clear
  D)
   8 done clear
  View Solution play_arrow