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Test : Chapter 1 — Electric Field, Maximum Marks: 50, , Duration: 60 minutes, , Time: 6 PM-7 PM, , Q.1 Electric field lines provide information about, (a) field strength, , (b) direction, , (c) nature of charge, , (d) all of these, , Q.2 The unit of electric dipole moment is, (a) newton, , (b) coulomb, , (c) farad, , (d) debye, , Q.3 Consider a region inside which, there are various types of charges but the total charge is, Zero. At points outside the region, , (a) the electric field is necessarily zero., , (b) the electric field is due to the dipole moment of the charge distribution only., , (c) the dominant electric field is inversely pro-portional to r°, for large r (distance from ori-gin)., (d) the work done to move a charged particle along a closed path, away from the region will not, be zero., , Q.4 SI unit of permittivity of free space is, (a) Farad, , (b) Weber, , (c) C?N* m*, , (d) C?N' m?, , Q.5A body gets positive charge, it means that, (a) it has lost electrons,, , (b) it has gained electrons., , (c) it has gained positrons., , (d) it has gained alpha particles., , Q.6 The minimum value of charge on any charged body may be, (a) 1.6 * 10°" coulomb, , (b) 1 coulomb, , (c) 1 * 10° Coulomb, , (d) 4.8 * 10°? Coulomb
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Q.7 When a glass rod is rubbed with silk, it, (a) gains electrons from silk., , (b) gives electrons to silk., , (c) gains protons from silk., , (d) gives protons to silk., , Q.8 Two charges q1 and q2 are placed in vacuum at a distance d and the force acting between, them is F. If a medium of dielectric constant 4 is introduced around them, the force now will be, (a) F/4 the presence of medium, force becomes 1/K time, , (b) F/2 the presence of medium, force becomes 2/K time, , (c)0, , (d) None, , , , Q.9 When 10” electrons are removed from a neutral metal sphere, the charge on the sphere, becomes, , (a) As electrons are removed, so charge will be positive., , (b) 1 coulomb, , (c) 1 * 10° Coulomb, , (d) None, , , , Q.10 Two similar spheres having +Q and -Q charges are kept at a certain distance. F force acts, between the two. If at the middle of two spheres, another similar sphere having +Q charge is, kept. then it experiences a force in magnitude and direction as, , (a) zero having no direction., , (b) 8F towards +Q charge., , (c) 8F towards -Q charge., , (d) 4F towards +Q charge., , Q.11 Acharge Q is divided into two parts of q and Q — q. If the coulomb repulsion between them, when they are separated is to be maximum, the ratio of Q/q should be, , (a) 2:1, , (b) 1/2, , (c) 4:1, , (d)%, , Q.12 Four equal charges q are placed at the four comers A, B, C, D of a square of length a. The, magnitude of the force on the charge at B will be
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4 iB, . ls, jc, 7. 4, (e) 5 wo 4, fxea? 4reya”, (2zt 2, Tyg? \ v2, © (+2) Li w f, 2s dee,a' Araya, , Q.13 Two charges of equal magnitudes kept at a distance r exert a force F on each other. If the, charges are halved and distance between them is doubled, then the new force acting on each, charge is, , F F, @ 7 ® =, , £, (e) 4F Ws, , Q.14 The electric field inside a spherical shell of uniform surface charge density is, (a) zero., , (b) constant, less than zero., , (c) directly proportional to the distance from the centre., , (d) none of the these, , Q.15 Electric field at a point varies as r° for, (a) an electric dipole, , (b) a point charge, , (c) a plane infinite sheet of charge, , (d) a line charge of infinite length, , Q.16 The electric field intensity due to an infinite cylinder of radius R and having charge q per, unit length at a distance rir r(r > R) from its axis is, , (a) directly proportional to r., , (b) directly proportional to r3., , (c) inversely proportional to r., , (d) inversely proportional to r°., , Q.17 Which of the following graphs shows the variation of electric field E due to a hollow, spherical conductor of radius R as a function of distance from the centre of the sphere?
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(a) of, , , , Q.18 ect? The electric field at a point is, , (a) always continuous., , (b) continuous if there is a charge at that point., , (c) discontinuous only if there is a negative charge at that point., (d) discontinuous if there is a charge at that point., , Q.19 A charge Q is placed at the centre of the line joining two point charges +q and +q as, shown in the figure. The ratio of charges Q and q is, , (a) 4, (b) 1/4, (c) -4, (d) -%, , Q.20 The force per unit charge is known as, (a) electric flux, , (b) electric field, , (c) electric potential, , (d) electric current, , Q.21 Electric field lines provide information about, (a) field strength, , (b) direction, , (c) nature of charge, , (d) all of these
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Q.22 Which of the following figures represent the electric field lines due to a single negative, charge?, , « oe wy) ote, *, , Ae, , — —s, — —>, 4 <-© WO, : =, - >, , Q.23 What is the cause of quantisation of electric charge?, , (a) The minimum charge that is stable, is charge of an electron. Since, electrons are transferred, from one object to another, therefore, electric charge is said to be quantised., , (b) direction, , (c) nature of charge, , (d) all of these, , Q.24 What do you mean by conservative nature of the electric force?, , (a) field strength, , (b) The electric force is conservative in nature, because the work done by it in moving a charge, is path independent., , (c) nature of charge, , (d) Electric current, , Q.25 What is the limitation of Coulomb's law?, (a) Flux, , (b) direction, , (c) Itis applied only for point charges., , (d) all of these
