12th Class Physics Electrostatics & Capacitance Question Bank

done Case Based (MCQs) - Electrostatic Potential and Capacitance Total Questions - 50

• question_answer1)

  Direction: Q.1 to Q.5

  The potential at any observation point P of a static electric field is defined as the work done by the external agent (or negative of work done by electrostatic field) in slowly bringing a unit positive point charge from infinity to the observation point. Figure shows the potential variation along the line of charges. Two point charges \[{{Q}_{1}}\], and \[{{Q}_{2}}\]lie along a line at a distance from each other.

  Read the given passage carefully and give the answer of the following questions.

  At which of the points 1, 2 and 3 is the electric field is zero?
  A)
  1   done clear
  B)
  2           done clear
  C)
  3                      done clear
  D)
  Both (a) and done clear
  View Solution play_arrow

• question_answer2)
  The signs of charges \[{{Q}_{1}}\] and \[{{Q}_{2}}\] respectively are:
  A)
  positive and negative      done clear
  B)
  negative and positive done clear
  C)
  positive and positive done clear
  D)
  negative and negative done clear
  View Solution play_arrow

• question_answer3)
                               Which of the two charges \[{{Q}_{1}}\] and \[{{Q}_{2}}\] is greater in magnitude?
  A)
  \[{{Q}_{2}}\]                            done clear
  B)
  \[{{Q}_{1}}\] done clear
  C)
  Same                done clear
  D)
  Can't determined done clear
  View Solution play_arrow

• question_answer4)
  Which of the following statement is not true?
  A)
  Electrostatic force is a conservative force done clear
  B)
  Potential energy of charge q at a point is the work done per unit charge in bringing a charge from any point to infinity done clear
  C)
  When two like charges lie infinite distance apart, their potential energy is zero done clear
  D)
  Both (a) and (c) done clear
  View Solution play_arrow

• question_answer5)
  Positive and negative charges of equal magnitude are kept at \[\left( 0,\,0,\,\frac{a}{2} \right)\]and \[\left( 0,\,0,\,\frac{-a}{2} \right)\] respectively. The work done by the electric field when another positive point charge is moved from (-0,0,0) to (0, a, 0) is:
  A)
  positive               done clear
  B)
  negative done clear
  C)
  zero done clear
  D)
  depends on the path connecting the initial and final positions done clear
  View Solution play_arrow

• question_answer6)

  Direction: Q.6 to Q.10

  Potential difference \[\left( \Delta V \right)\]between two points A and B separated by a distance x, in a uniform electric field E is given by \[\Delta V=-Ex\]where x is measured parallel to the field lines. If a charge \[{{q}_{0}}\]moves from P to Q, the change in potential energy \[\left( \Delta U \right)\]is given as \[\Delta U={{q}_{0}}\Delta V\]. A proton is released from rest in uniform electric field of magnitude \[4.0\times {{10}^{8}}V{{m}^{-1}}\]directed along the positive X-axis. The proton undergoes a displacement of 0.25 m in the direction of E.

  Mass of a proton \[=1.66\times {{10}^{-27}}kg\]and charge of proton\[=1.6\times {{10}^{-19}}C\]

  Read the given passage carefully and give the answer of the following questions.

  The change in electric potential of the proton between the points A and B is:
  A)
  \[-1\times {{10}^{8}}V\] done clear
  B)
    \[1\times {{10}^{8}}V\] done clear
  C)
  \[6.4\times {{10}^{-19}}V\]      done clear
  D)
  \[-6.4\times {{10}^{-19}}V\] done clear
  View Solution play_arrow

• question_answer7)
  The change in electric potential energy of the proton for displacement from A to B is:
  A)
  \[1.6\times {{10}^{11}}J\]                    done clear
  B)
  \[0.5\times {{10}^{23}}J\] done clear
  C)
  \[-1.6\times {{10}^{-11}}J\]      done clear
  D)
  \[3.2\times {{10}^{22}}J\] done clear
  View Solution play_arrow

• question_answer8)
  The mutual electrostatic potential energy between two protons which are at a distance of \[9\times {{10}^{-15}}m\], in \[_{92}{{U}^{235}}\]nucleus is:
  A)
  \[1.56\,\times {{10}^{-14}}J\]   done clear
  B)
  \[5.5\times {{10}^{-14}}J\] done clear
  C)
  \[2.56\times {{10}^{-14}}J\]     done clear
  D)
  \[4.56\times {{10}^{-14}}J\] done clear
  View Solution play_arrow

• question_answer9)
  If a system consists of two charges 4 mC and -3 mC with no external field placed at (-5 cm, 0, 0) and (5 cm, 0, 0) respectively. The amount of work required to separate the two charges infinitely away from each other is:
  A)
  -1.1 J done clear
  B)
  2 J done clear
  C)
  2.5 J done clear
  D)
  3 J done clear
  View Solution play_arrow

• question_answer10)
  As the proton moves from P to Q, then:
  A)
  the potential energy of proton decreases done clear
  B)
  the potential energy of proton increases done clear
  C)
  the proton Loses kinetic energy done clear
  D)
  total energy of the proton increases done clear
  View Solution play_arrow

• question_answer11)

  Direction: Q.11 to Q.15

  This energy possessed by a system of charges by virtue of their positions. When two like charges lie infinite distance apart, their potential energy is zero because no work has to be done in moving one charge at infinite distance from the other.

  In carrying a charge q from point A to point B, work done\[W=q\left( {{V}_{A}}-{{V}_{B}} \right)\]. This work may appear as change in KE/PE of the charge. The potential energy of two charges \[{{q}_{1}}\]and \[{{q}_{2}}\]at a distance r in air is\[\frac{{{q}_{1}}{{q}_{2}}}{4\pi {{\varepsilon }_{0}}r}\]. It is measured in joule. It may be positive, negative or zero depending on the signs of \[{{q}_{1}}\]and \[{{q}_{2}}\].

  Read the given passage carefully and give the answer of the following questions.

  Calculate work done in separating two electrons form a distance of 1 m to 2 m in air, where e is electric charge and k is electrostatic force constant.
  A)
  \[k{{e}^{2}}\]                          done clear
  B)
  \[{{e}^{2}}/2\] done clear
  C)
  \[-k{{e}^{2}}/2\]                      done clear
  D)
  zero done clear
  View Solution play_arrow

• question_answer12)
  Four equal charges q each are placed at four corners of a square of side a each. Work done in carrying a charge –q from its centre to infinity is:
  A)
  zero                               done clear
  B)
  \[\frac{\sqrt{2}{{q}^{2}}}{\pi {{\varepsilon }_{0}}a}\] done clear
  C)
  \[\frac{\sqrt{2}q}{\pi {{\varepsilon }_{0}}a}\]                  done clear
  D)
  \[\frac{{{q}^{2}}}{\pi {{\varepsilon }_{0}}a}\] done clear
  View Solution play_arrow

• question_answer13)
  Two points A and B are located in diametrically opposite directions of a point charge \[+2\mu C\]at distances 2 m and 1 m respectively from it. The potential difference between A and S is:
  A)
  \[3\times {{10}^{3}}V\]                        done clear
  B)
  \[6\times {{10}^{4}}V\] done clear
  C)
  \[-9\times {{10}^{3}}V\]                       done clear
  D)
  \[-3\times {{10}^{3}}V\] done clear
  View Solution play_arrow

• question_answer14)
  Two points charges \[A=+3nC\]and \[B=+1\text{ }nC\]are placed 5 cm apart in air. The work done to move charge B towards A by 1 cm is;
  A)
  \[2.0\times {{10}^{-7}}J\] done clear
  B)
    \[1.35\times {{10}^{-7}}J\] done clear
  C)
  \[2.7\times {{10}^{-7}}J\]                     done clear
  D)
  \[12.1\times {{10}^{-7}}J\] done clear
  View Solution play_arrow

• question_answer15)
  A charge Q is placed at the origin. The electric potential due to this charge at a given point in space is V. The work done by an external force in bringing another charge q from infinity up to the point is:
  A)
  \[\frac{V}{q}\]                           done clear
  B)
  Vq done clear
  C)
  \[V+q\]             done clear
  D)
  V done clear
  View Solution play_arrow

• question_answer16)

  Direction: Q.16 to Q.20

  When an insulator is placed in an external field, the dipoles become aligned. Induced surface charges on the insulator establish a polarization field \[{{\overrightarrow{E}}_{i}}\] in its interior.

  The net field \[\overrightarrow{E}\]in the insulator is the vector sum of \[{{\overrightarrow{E}}_{0}}\] and \[{{\overrightarrow{E}}_{i}}\]as shown in the figure.

  On the application of external electric field, the effect of aligning the electric dipoles in the insulator is called polarisation and the field \[{{\overrightarrow{E}}_{i}}\] is known as the polarization field.

  The dipole moment per unit volume of the dielectric is  known as polarisation \[\left( \overrightarrow{P} \right)\].

  For linear isotropic dielectrics, \[\overrightarrow{P}=\chi \overrightarrow{E}\], where \[\chi \] = electrical susceptibility of the dielectric medium.

  Read the given passage carefully and give the answer of the following questions.

  Which among the following is an example of polar molecule?
  A)
  \[{{O}_{2}}\]                            done clear
  B)
  \[{{H}_{2}}\] done clear
  C)
  \[{{N}_{2}}\]                            done clear
  D)
  \[HCl\] done clear
  View Solution play_arrow

• question_answer17)
  When air is replaced by a dielectric medium of constant K, the maximum force of attraction between two charges separated by a distance:
  A)
  increases K times    done clear
  B)
  remains unchanged done clear
  C)
  decreases K times    done clear
  D)
  increases 2K times done clear
  View Solution play_arrow

• question_answer18)
  Which of the following is a dielectric?
  A)
  Copper                 done clear
  B)
  Glass done clear
  C)
  Antimony (Sb)        done clear
  D)
    None of these done clear
  View Solution play_arrow

• question_answer19)
  For a polar molecule, which, of the following statements is true?
  A)
  The centre of gravity of electrons and protons coincide done clear
  B)
  The centre of gravity of electrons and protons do not coincide done clear
  C)
  The charge distribution is always symmetrical done clear
  D)
  The dipole moment is always zero done clear
  View Solution play_arrow

• question_answer20)
  When a comb rubbed with dry hair attracts pieces of paper. This is because the:
  A)
  comb polarizes 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_answer21)

  Direction: Q.21 to Q.25

  The electrical capacitance of a conductor is the measure of its ability to hold electric charge. An isolated spherical conductor of radius R. The charge Q is uniformly distributed over its entire surface. It can be assumed to be concentrated at the centre of the sphere. The potential at any point on the surface of the spherical conductor will be

  \[V=\frac{1}{4\pi {{\varepsilon }_{0}}}\frac{Q}{R}\].

  Capacitance of the spherical conductor situated in vacuum is

  \[C=\frac{Q}{V}=\frac{Q}{\frac{1}{4\pi {{\varepsilon }_{0}}}.\frac{Q}{R}}\] or \[C=4\pi {{\varepsilon }_{0}}R\]

  Clearly, the capacitance of a spherical conductor is proportional to its radius.

  The radius of the spherical conductor is 1 F capacitance is \[R=\frac{1}{4\pi {{\varepsilon }_{0}}}.C\]and this radius is about 1500 times the radius of earth\[\left( \tilde{\ }6\times {{10}^{3}}\,km \right)\].

  Read the given passage carefully and give the answer of the following questions.

  If an isolated sphere has a capacitance 50 pF then radius is:
  A)
  90 cm                           done clear
  B)
  45 cm done clear
  C)
  45 m                             done clear
  D)
  90 m done clear
  View Solution play_arrow

• question_answer22)
  How much charge should be placed on a capacitance of 25 pF to raise its potential to \[{{10}^{5}}V?\]
  A)
  \[1\mu C\]                      done clear
  B)
  \[1.5\,\mu C\] done clear
  C)
  \[2\mu C\]                      done clear
  D)
  \[2.5\mu C\] done clear
  View Solution play_arrow

• question_answer23)
  Dimensions of capacitance is:
  A)
  \[\left[ M{{L}^{-2}}{{T}^{4}}{{A}^{2}} \right]\]       done clear
  B)
  \[\left[ {{M}^{-1}}{{L}^{-1}}{{T}^{3}}{{A}^{1}} \right]\] done clear
  C)
  \[\left[ {{M}^{-1}}{{L}^{-2}}{{T}^{4}}{{A}^{2}} \right]\]   done clear
  D)
  \[\left[ {{M}^{0}}{{L}^{-2}}{{T}^{4}}{{A}^{1}} \right]\] done clear
  View Solution play_arrow

• question_answer24)
  Metallic sphere of radius R is charged to potential V. Then charge q is proportional to:
  A)
  V                                  done clear
  B)
  R done clear
  C)
  Both (a) and (b)      done clear
  D)
    None of these done clear
  View Solution play_arrow

• question_answer25)
  If 64 identical spheres of charge q and capacitance C each are combined to form a Large sphere. The charge and capacitance of the large sphere is:
  A)
  \[64q,\,C\]                      done clear
  B)
  \[16q,\,4C\] done clear
  C)
  \[64q,\,4C\]                    done clear
  D)
  \[16q,\,64C\] done clear
  View Solution play_arrow

• question_answer26)

  Direction: Q.26 to Q.30

  Surface charge density is defined as charge per unit surface area of surface charge distribution, i.e.,\[\sigma =\frac{dq}{ds}\]. 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 having magnitude of \[17.0\times {{10}^{-22}}C{{m}^{-2}}\]as shown. The intensity of electric field at a point is\[E=\frac{\sigma }{{{\varepsilon }_{0}}}\],

  where,\[{{\varepsilon }_{0}}\]= permittivity of free space.

  Read the given passage carefully and give the answer of the following questions.

  E in the outer region of the first plate is:
  A)
  \[17\times {{10}^{-22}}N/C\] done clear
  B)
  \[1.5\times {{10}^{-15}}N/C\] done clear
  C)
  \[1.9\times {{10}^{-10}}N/C\]    done clear
  D)
  zero done clear
  View Solution play_arrow

• question_answer27)
  E fin the outer region of the second plate is:
  A)
  \[17\times {{10}^{-22}}N/C\]    done clear
  B)
  \[1.5\times {{10}^{-15}}N/C\] done clear
  C)
  \[1.9\times {{10}^{-10}}N/C\]    done clear
  D)
  zero done clear
  View Solution play_arrow

• question_answer28)
  E between the plates is:
  A)
  \[17\times {{10}^{-22}}N/C\]    done clear
  B)
  \[1.5\times {{10}^{-15}}N/C\] done clear
  C)
  \[1.9\times {{10}^{-10}}N/C\]    done clear
  D)
  zero done clear
  View Solution play_arrow

• question_answer29)
  The ratio of E from right side of B at distances 2 cm and 4 cm respectively, is:
  A)
  1 : 2                              done clear
  B)
  2 : 1       done clear
  C)
  1 : 1                  done clear
  D)
  \[1:\sqrt{2}\] done clear
  View Solution play_arrow

• question_answer30)
  In order to estimate the electric field due to a thin finite plane metal plate, the Gaussian surface considered is:
  A)
  spherical                 done clear
  B)
  cylindrical  done clear
  C)
  straight line             done clear
  D)
  None of these done clear
  View Solution play_arrow

• question_answer31)

  Direction: Q.31 to Q.35

  The simplest and the most widely used capacitor is the parallel plate capacitor. It consists of two large plane parallel conducting plates, separated by a small distance.

  In the outer regions above the upper plate and below the lower plate, the electric fields due to the two charged plates cancel out. The net field is zero.

  In the inner region between the two capacitor plates, the electric fields due to the two charged plates add up. The net field is \[\frac{\sigma }{{{\varepsilon }_{0}}}\].

  For a uniform electric field, potential difference between the plates = Electric field \[\times \] distance between the plates.

  Capacitance of the parallel plate capacitor is, the charge required to supplied to either of the conductors of the capacitor so as to increase the potential difference between, then by unit amount.

  Read the given passage carefully and give the answer of the following questions.

  A parallel plate capacitor is charged and then isolated. The effect of increasing the plate separation on charge, potential and capacitance respectively are:
  A)
  increases, decreases, decreases done clear
  B)
  constant, increases, decreases done clear
  C)
  constant, decreases, decreases done clear
  D)
  constant, decreases, increases done clear
  View Solution play_arrow

• question_answer32)
  In a parallel plate capacitor, the capacity increases if:
  A)
  area of the plate is decreases done clear
  B)
  distance between the plates increases                  done clear
  C)
  area of the plate is increases done clear
  D)
  dielectric constant decreases done clear
  View Solution play_arrow

• question_answer33)
  A parallel plate capacitor has two square plates with equal and opposite charges. The surface charge densities on the plates are \[+\sigma \] and \[-\sigma \] respectively. In the region between the plates the magnitude of the electric field is:
  A)
  \[\frac{\sigma }{2{{\varepsilon }_{0}}}\]             done clear
  B)
  \[\frac{\sigma }{{{\varepsilon }_{0}}}\] done clear
  C)
  0                                  done clear
  D)
  None of these done clear
  View Solution play_arrow

• question_answer34)
  If a parallel plate air capacitor consists of two circular plates of diameter 8 cm. At what distance should the plate be held so as to have the same capacitance as that of sphere of diameter 20 cm?                         
  A)
  9 mm                            done clear
  B)
  4 mm      done clear
  C)
  8 mm                            done clear
  D)
  2 mm done clear
  View Solution play_arrow

• question_answer35)
  If a charge of \[+2.0\times {{10}^{-8}}C\]is placed on the positive plate and a charge of \[-1.0\times {{10}^{-8}}C\]on the negative plate of a parallel plate capacitor of capacitance\[1.2\times {{10}^{-3}}\mu F\], then the potential difference developed between the plates is:
  A)
  6.25V                            done clear
  B)
  3.0V      done clear
  C)
  12.5 V                           done clear
  D)
  25V done clear
  View Solution play_arrow

• question_answer36)

  Direction: Q.36 to Q.40

  A dielectric slab is a substance which does not allow the flow of charges through it but permits them to exert electrostatic forces on one another.

  When a dielectric slab is placed between the plates, the field \[{{E}_{0}}\]polarises the dielectric. This induce charge \[-{{Q}_{P}}\]on the upper surface are \[+{{Q}_{P}}\]on the lower surface of the dielectric. These induced charges set up a field \[{{E}_{P}}\]inside the dielectric in the opposite direction of \[{{\overrightarrow{E}}_{0}}\] as shown.

  Read the given passage carefully and give the answer of the following questions.

  In a parallel plate capacitor, the capacitance increases from \[4\mu F\] to \[80\mu F\], on introducing a dielectric medium between the plates. What is the dielectric constant of the medium?
  A)
  10                                 done clear
  B)
  20 done clear
  C)
  50                                 done clear
  D)
  100 done clear
  View Solution play_arrow

• question_answer37)
  A parallel plate capacitor with air between the plates has a capacitance of 8 pF. The separation between the plates is now reduced half and the space between them is filled with a medium of dielectric constant 5. Calculate the value of capacitance of the capacitor in second case.
  A)
  BpF                              done clear
  B)
  10pF      done clear
  C)
  80 pF                            done clear
  D)
  100 pF      done clear
  View Solution play_arrow

• question_answer38)
  A dielectric introduced between the plates of a parallel plate condenser:
  A)
  decreases the electric field between the plates           done clear
  B)
  increases the capacity of the condenser                done clear
  C)
  increases the charge stored in the condenser done clear
  D)
  increases the capacity of the condenser done clear
  View Solution play_arrow

• question_answer39)
  A parallel plate capacitor of capacitance 1pF has separation between the plates is (d) When the distance of separation becomes 2d and wax of dielectric constant x is inserted in it the capacitance becomes 2 pF. What is the value of x?
  A)
  2                      done clear
  B)
  4           done clear
  C)
  6                      done clear
  D)
  8 done clear
  View Solution play_arrow

• question_answer40)
  A parallel plate capacitor having area A and separated by distance d is filled by copper plate of thickness b. The new capacity is:                                            
  A)
  \[\frac{{{\varepsilon }_{0}}A}{d+\frac{b}{2}}\]             done clear
  B)
  \[\frac{{{\varepsilon }_{0}}A}{2d}\] done clear
  C)
  \[\frac{{{\varepsilon }_{0}}A}{d-b}\]                  done clear
  D)
  \[\frac{2{{\varepsilon }_{0}}A}{d+\frac{b}{2}}\] done clear
  View Solution play_arrow

• question_answer41)

  Direction: Q.41 to Q.45

  An arrangement of two conductors separated by an insulating medium can be used to store electric charge and electric energy. Such a system is called a capacitor. The more charge a capacitor can store, the greater is its capacitance. Usually, a capacitor consists of two conductors having equal and opposite charge +Q and -Q.

  Hence, there is a potential difference V between them. By the capacitance of a capacitor, we mean the ratio of the charge Q to the potential difference V. By the charge on a capacitor we mean only the charge Q on the positive plate. Total charge of the capacitor is zero. The capacitance of a capacitor is a constant and depends on geometric factors, such as the shape, size and relative position of the two conductors, and the nature of the medium between them. The unit of capacitance is farad (F), but the more convenient units are \[\mu F\]and pF. A commonly used capacitor consists of two long strips or metal foils, separated by two long strips of dielectrics, rolled up into a small cylinder. Common dielectric materials are plastics (such as polyesters and polycarbonates) and aluminium oxide. Capacitors are widely used in television, computer, and other electric circuits.

  Read the given passage carefully and give the answer of the following questions.

  A parallel plate capacitor C has a charge Q/2. The actual charges on its plates are:
  A)
  0.0                                done clear
  B)
  \[Q/2,\,Q/2\] done clear
  C)
  \[Q,-Q\]                         done clear
  D)
  \[Q/2,-Q/2\] done clear
  View Solution play_arrow

• question_answer42)
  A parallel plate capacitor is charged. If the plates are pulled apart:
  A)
  the capacitance increases done clear
  B)
  the potential difference increases done clear
  C)
  the total charge increases done clear
  D)
  the charge and potential difference remain the same. done clear
  View Solution play_arrow

• question_answer43)
  If n capacitors, each of capacitance C, are connected in series, then the equivalent capacitance of the combination will be:
  A)
  \[nC\]    done clear
  B)
    \[{{n}^{2}}C\] done clear
  C)
  \[C/n\]               done clear
  D)
  \[C/{{n}^{2}}\] done clear
  View Solution play_arrow

• question_answer44)
  Three capacitons of 2.0, 5.0 and \[6.0\mu F\]are connected in series to a 10 V source. The charge on the \[3.0\mu F\]capacitor is :
  A)
  \[5\mu C\]                      done clear
  B)
  \[10\mu C\] done clear
  C)
  \[12\mu C\]                    done clear
  D)
  \[15\mu C\] done clear
  View Solution play_arrow

• question_answer45)
  What is the potential difference across \[2\mu F\]capacitor in the circuit shown?
  A)
  12 V     done clear
  B)
    4 V done clear
  C)
  6 V                               done clear
  D)
  18 V done clear
  View Solution play_arrow

• question_answer46)

  Direction: Q.46 to Q.50

  A capacitor is a device to store energy. The process of charging up a capacitor involves the transferring of electric charges from its one place to another. This work done in charging the capacitor is stored as its electrical potential energy.

  If q is the charge and V is the potential difference across a capacitor at any instant during its charging, then small work done in storing an additional small charge dq against the repulsion of charge q already stored on it is \[dW=V.dq=\left( q/C \right)dq.\]

  Read the given passage carefully and give the answer of the following questions.

  A system of 2 capacitors of capacitance \[2\mu F\]and \[4\mu F\]is connected in series across a potential difference of 6 V. The energy stored in the system is:
  A)
  \[3\mu J\]                                  done clear
  B)
  \[24\mu J\] done clear
  C)
  \[30\mu J\]                     done clear
  D)
  \[108\,\mu J\] done clear
  View Solution play_arrow

• question_answer47)
  A capacitor of capacitance of \[10\mu F\]is charged to 10 V. The energy stored in it is:
  A)
  \[100\mu J\]                   done clear
  B)
  \[500\mu J\] done clear
  C)
  \[1000\mu J\]                 done clear
  D)
  \[1\mu J\] done clear
  View Solution play_arrow

• question_answer48)
  A parallel plate air capacitor has capacity C farad, potential V volt and energy E joule. When the gap between the plates is completely filled with dielectric:
  A)
  Both V and E increase     done clear
  B)
  Both V and E decrease done clear
  C)
  V decreases, F increases   done clear
  D)
  V increases, £ decreases done clear
  View Solution play_arrow

• question_answer49)
  A capacitor with capacitance \[5\mu F\]is charged to \[5\mu C\]If the plates are pulled apart to reduce the capacitance to \[2\mu F\]how much work is done?
  A)
  \[6.25\times {{10}^{-6}}J\]       done clear
  B)
  \[3.75\times {{10}^{-6}}J\] done clear
  C)
  \[2.16\times {{10}^{-6}}J\]       done clear
  D)
  \[2.55\times {{10}^{-6}}J\] done clear
  View Solution play_arrow

• question_answer50)
  A metallic sphere of radius 18 cm has been given a charge of \[5\times {{10}^{-6}}C\]. The energy of the charged conductor is:
  A)
  0.2J                              done clear
  B)
  06 J done clear
  C)
  1.2J                              done clear
  D)
  2.4J done clear
  View Solution play_arrow