CUET Physics MCQs Unit I Electrostatics

CUET Physics Electric Charges and Fields MCQs

Question: Charge is the property associated with matter due to which it produces and experiences

(a) electric effects only

(b) magnetic effects only

(c) both electric and magnetic effects

(d) None of these

Answer: C

Question: A point charge is kept at the centre of metallic insulated spherical shell. Then

(a) electric field out side the sphere is zero

(b) electric field inside the sphere is zero

(c) net induced charge on the sphere is zero

(d) electric potential inside the sphere is zero

Answer: C

Question: In figure two positive charges q₂ and q₃ fixed along the y-axis, exert a net electric force in the + x-direction on a charge q₁ fixed along the x-axis. If a positive charge Q is added at (x, 0), the force on q₁

(a) shall increase along the positive x-axis

(b) shall decrease along the positive x-axis

(c) shall point along the negative x-axis

(d) shall increase but the direction changes because of the intersection of Q with q₂ and q₃

Answer: A

Question:

(a) 3

(b) 5

(c) 2

(d) 7

Answer: C

Question: A body is positively charged, it implies that

(a) there is only positive charge in the body.

(b) there is positive as well as negative charge in the body but the positive charge is more than negative charge

(c) there is equal positive and negative charge in the body but the positive charge lies in the outer regions

(d) negative charge is displaced from its position

Answer: B

Question: If an object possesses an electric charge, it is said to be electrified or ... A ... When it has no charge, it is said to be ... B ... Here, A and B refer to

(a) charged, neutral

(b) neutral, charged

(c) discharged, charged

(d) active, reactive

Answer: A

Question: Quantisation of charge was experimentally demonstrated by

(a) Einstein’s photoelectric effect

(b) Frank-Hertz experiment

(c) Davisson and Germer experiment

(d) Millikan’s oil drop experiment

Answer: D

Question: What happens when some charge is placed on a soap bubble?

(a) Its radius decreases

(b) Its radius increases

(c) The bubble collapses

(d) None of these

Answer: B

Question: A charged particle is free to move in an electric field. It will travel

(a) always along a line of force

(b) along a line of force, if its initial velocity is zero

(c) along a line of force, if it has some initial velocity in the

direction of an acute angle with the line of force

(d) none of the above

Answer: B

Question: Electric lines of force

(a) exist everywhere

(b) exist only in the immediate vicinity of electric charges

(c) exist only when both positive and negative charges are near one another

(d) are imaginary

Answer: D

Question: For distance far away from centre of dipole the change in magnitude of electric field with change in distance from the centre of dipole is

(a) zero.

(b) same in equatorial plane as well as axis of dipole.

(c) more in case of equatorial plane of dipole as compared to axis of dipole.

(d) more in case of axis of dipole as compared to equatorial plane

Answer: D

Question: An electric dipole will experience a net force when it is placed in

(a) a uniform electric field

(b) a non-uniform electric field

(c) both (a) and (b)

(d) None of these

Answer: B

Question: Gauss’s law is true only if force due to a charge varies as

(a) r^–1

(b) r^–2

(c) r^–3

(d) r^–4

Answer: B

Question: The Gaussian surface

(a) can pass through a continuous charge distribution.

(b) cannot pass through a continuous charge distribution.

(c) can pass through any system of discrete charges.

(d) can pass through a continuous charge distribution as well as any system of discrete charges.  

Answer: B

Question:  Assertion : On moving a distance two times the initial distance away from an infinitely long straight uniformly charged wire the electric field reduces to one third of the initial value.

Reason : The electric field is inversely proportional to the distance from an infinitely long straight uniformly charged wire.

(a) Assertion is correct, reason is correct; reason is a correct explanation for assertion.

(b) Assertion is correct, reason is correct; reason is not a correct explanation for assertion

(c) Assertion is correct, reason is incorrect

(d) Assertion is incorrect, reason is correct.

Answer: A

Question:  Two small balls having the same mass and charge and located on the same vertical at heights h₁ and h₂ are thrown in the same direction along the horizontal at the same velocity v. The first ball touches the ground at a distance l from the initial vertical. At what height H₂ will the second ball be at this instant ? The air drag and the effect of the charges induced on the ground should be neglected.

Answer: A

Question: 

Answer: A

Question: The electric flux through the surface

(a) in Fig. (iv) is the largest

(b) in Fig. (iii) is the least

(c) in Fig. (ii) is same as Fig. (iii) but is smaller than Fig. (iv)

(d) is the same for all the figures

Answer: D

Question:

(a) reduces by 70.7%

(b) reduces by 29.3%

(c) reduces by 9.7%

(d) reduces by 14.6%

Answer: A

Question: Which of the following is the best insulator?

(a) Carbon

(b) Paper

(c) Graphite

(d) Ebonite

Answer: D

Question: A positively charged rod is brought near an uncharged conductor. If the rod is then suddenly withdrawn, the charge left on the conductor will be

(a) positive

(b) negative

(c) zero

(d) cannot say

Answer: C

Question: In annihilation process, in which an electron and a positron transform into two gamma rays, which property of electric charge is displayed?

(a) Additivity of charge

(b) Quantisation of charge

(c) Conservation of charge

(d) Attraction and repulsion

Answer: C

Question: An electric field can deflect

(a) neutrons

(b) X-rays

(c) γ-rays

(d) α-particles

Answer: D

Question: If one penetrates a uniformly charged spherical cloud, electric field strength

(a) decreases directly as the distance from the centre

(b) increases directly as the distance from the centre

(c) remains constant

(d) None of these

Answer: A

Question: Electric flux over a surface in an electric field may be

(a) positive

(b) negative

(c) zero

(d) All of the above

Answer: D

Question: The formation of a dipole is due to two equal and dissimilar point charges placed at a

(a) short distance

(b) long distance

(c) above each other

(d) none of these

Answer: A

Question: An electric dipole is placed at the centre of a sphere then

(a) the flux of the electric field through the sphere is not zero.

(b) the electric field is zero at every point of the sphere.

(c) the electric field is not zero anywhere on the sphere.

(d) the electric field is zero on a circle on the sphere.

Answer: A

Question: 

Answer: C

Question: 

Answer: B

Question: A point charge + q is placed at a distance d from an isolated conducting plane. The field at a point P on the other side of the plane is

(a) directed perpendicular to the plane and away from the plane

(b) directed perpendicular to the plane but towards the plane

(c) directed radially away from the point charge

(d) directed radially towards the point charge

Answer: A

Question: On rubbing, when one body gets positively charged and other negatively charged, the electrons transferred from positively charged body to negatively charged body are

(a) valence electrons only

(b) electrons of inner shells

(c) both valence electrons and electrons of inner shell

(d) yet to be established

Answer: A

Question: Quantisation of charge implies

(a) charge cannot be destroyed

(b) charge exists on particles

(c) there is a minimum permissible charge on a particle

(d) charge, which is a fraction of a coulomb is not possible.

Answer: D

Question: The value of electric permittivity of free space is

(a) 9 × 10⁹ NC²/m²

(b) 8.85 × 10^–12Nm²/C² sec

(c) 8.85 × 10^–12 C²/Nm²

(d) 9 × 109C²/Nm²

Answer: C

Question: If an electron has an initial velocity in a direction different from that of an electric field, the path of the electron is

(a) a straight line
(b) a circle

(c) an ellipse

(d) a parabola

Answer: D

Question: The electric field inside a spherical shell of uniform surface charge density is

(a) zero

(b) constant different from zero

(c) proportional to the distance from the curve

(d) None of the above

Answer: A

Question: A hollow sphere of charge does not have electric field at

(a) outer point

(b) interior point

(c) beyond 2 m

(d) beyond 100 m

Answer: B

Question: 

Answer: C

Question: 

Answer: A

Question: Assertion : The positive charge particle is placed in front of a spherical uncharged conductor. The number of lines of forces terminating on the sphere will be more than those emerging from it.
Reason : The surface charge density at a point on the sphere nearest to the point charge will be negative and maximum in magnitude compared to other points on the sphere.

(a) If both Assertion and Reason are correct and Reason is the correct explanation of Assertion.

(b) If both Assertion and Reason are correct, but Reason is not the correct explanation of Assertion.

(c) If Assertion is correct but Reason is incorrect.

(d) If both the Assertion and Reason are incorrect.

Answer: D

Question: When a body is charged by induction, then the body

(a) becomes neutral

(b) does not lose any charge

(c) loses whole of the charge on it

(d) loses part of the charge on it

Answer: B

Question: When some charge is transferred to ...A... it readily gets distributed over the entire surface of ... A... If some charge is put on ... B..., it stays at the same place.

Here, A and B refer to

(a) insulator, conductor

(b) conductor, insulator

(c) insulator, insulator

(d) conductor, conductor

Answer: B

Question: The unit of electric field is not equivalent to

(a) N / C

(b) J / C

(c) V / m

(d) J / Cm

Answer: B

Question: Positive electric flux indicates that electric lines of force are directed

(a) outwards
(b) inwards

(c) either (a) or
(b) (d) None of these

Answer: A

Question: The electric field at a point on equatorial line of a dipole and direction of the dipole moment

(a) will be parallel

(b) will be in opposite direction

(c) will be perpendicular

(d) are not related

Answer: B

Question: Charge motion within the Gaussian surface gives changing physical quantity

(a) electric field

(b) electric flux

(c) charge

(d) gaussian surface area

Answer: A

Question:   A charged particle q is placed at the centre O of cube of length L (A B C D E F G H). Another same charge q is placed at a distance L from O. Then the electric flux through ABCD is

Answer: B

Question: Figure shows electric field lines in which an electric dipole P is placed as shown. Which of the following statements is correct?

(a) The dipole will not experience any force

(b) The dipole will experience a force towards right

(c) The dipole will experience a force towards left

(d) The dipole will experience a force upwards

Answer: C

Question: On charging by conduction, mass of a body may

(a) increase

(b) decreases

(c) increase or decrease

(d) None of these

Answer: C

Question: Coulomb’s law is true for

(a) atomic distances (= 10^–11 m)

(b) nuclear distances (= 10^–15 m)

(c) charged as well as uncharged particles

(d) all the distances

Answer: A

Question: The S.I. unit of electric flux is

(a) weber

(b) newton per coulomb

(c) volt × metre

(d) joule per coulomb

Answer: C

Question: An electric dipole is placed at an angle of 30° to a non-uniform electric field. The dipole will experience

(a) a translational force only in the direction of the field

(b) a translational force only in the direction normal to the direction of the field

(c) a torque as well as a translational force

(d) a torque only

Answer: C

Question:  Two identical thin rings, each of radius a meter, are coaxially placed at a distance R meter apart. If Q₁ coulomb and Q₂ coulomb are respectively the charges uniformly spread on the two rings, the work done in moving a charge q coulomb from the centre of one ring to that of the other is

Answer: B

Question: A point positive charge is brought near an isolated conducting sphere (figure). The electric field is best given by

Answer: A

Question: Two spheres A and B of exactly same mass are given equal positive and negative charges respectively. Their masses after charging

(a) remains unaffected

(b) mass of A > mass of B

(c) mass of A < mass of B

(d) Nothing can be said

Answer: C

Question: If a linear isotropic dielectric is placed in an electric field of strength E, then the polarization P is

(a) independent of E

(b) inversely proportional to E

(c) directly proportional to E

(d) directly proportional to E

Answer: D

Question: A region surrounding a stationary electric dipoles has

(a) magnetic field only

(b) electric field only

(c) both electric and magnetic fields

(d) no electric and magnetic fields

Answer: B

Question: An electric dipole has a pair of equal and opposite point charges q and –q separated by a distance 2x. The axis of the dipole is

(a) from positive charge to negative charge

(b) from negative charge to positive charge

(c) Perpendicular to the line joining the two charges rawn at the centre and pointing upward direction

(d) Perpendicular to the line joining the two charges drawn at the centre and pointing downward direction

Answer: B

Question: An electron falls from rest through a vertical distance h in a uniform and vertically upward directed electric field E. The direction of electric field is now reversed, keeping its magnitude the same. A proton is allowed to fall from rest in it through the same vertical distance h. The time of fall of the electron, in comparison to the time of fall of the proton is

(a) smaller

(b) 5 times greater

(c) equal

(d) 10 times greater

Answer: A

Question: When a comb rubbed with dry hair attracts pieces of paper. This is because the

(a) comb polarizes the piece of paper

(b) comb induces a net dipole moment opposite to the direction of field

(c) electric field due to the comb is uniform

(d) comb induces a net dipole moment perpendicular to the direction of field

Answer: A

Question: Electric lines of force about a negative point charge are

(a) circular anticlockwise

(b) circular clockwise

(c) radial, inwards

(d) radial, outwards

Answer: C

Question: Gauss's law is valid for

(a) any closed surface

(b) only regular close surfaces

(c) any open surface

(d) only irregular open surfaces

Answer: A

Question:  A hemisphere is uniformely charged positively. The electric field at a point on a diameter away from the centre is directed

(a) perpendicular to the diameter

(b) parallel to the diameter

(c) at an angle tilted towards the diameter

(d) at an angle tilted away from the diameter

Answer: A

Question: The law, governing the force between electric charges is known as

(a) Ampere's law

(b) Ohm's law

(c) Faraday's law

(d) Coulomb's law

Answer: D

Question: If the flux of the electric field through a closed surface is zero, then

(a) the electric field must be zero everywhere on the surface

(b) the electric field may not be zero everywhere on the surface

(c) the charge inside the surface must be zero

(d) the charge in the vicinity of the surface must be zero

Answer: C

Question: 6 A particle of charge q and mass m moves rectilinearly under the action of electric field E = A – Bx, where A and B are positive constants and x is distance from the point where particle was initially at rest then the distance traveled by the particle before coming to rest and acceleration of particle at that moment are respectively :

Answer: C

Question: Charge is

(a) transferable

(b) associated with mass

(c) conserved

(d) All of these

Answer: D

Question: Debye is the unit of

(a) electric flux

(b) electric dipole moment

(c) electric potential

(d) electric field intensity

Answer: B

Question: Two point charges + Q and + q are separated by a certain distance. If + Q > + q then in between the charges the electric field is zero at a point

(a) closer to + Q

(b) closer to + q

(c) exactly at the mid-point of line segment joining + Q and + q.

(d) no where on the line segment joining + Q and + q.

Answer: C

Question: An electric dipole is kept in a non-uniform electric field. It experiences

(a) a force and a torque

(b) a force but not a torque

(c) a torque but no force

(d) neither a force nor a torque

Answer: A
 

CUET Physics Electrostatic Potential and Capacitance MCQs

Question: A hollow metal sphere of radius 5 cm is charged such that the potential on its surface is 10 V. The potential at a distance of 2 cm from the centre of the sphere is

(a) zero

(b) 10 V

(c) 4 V

(d) 10/3 V

Answer: B

Question: Consider the following statements and select the correct option

I. In an external electric field, the positive and negative charges of a non–polar molecule are displaced in opposite directions.

II. In non –polar molecules displacement stops when the external force on the constituent charges of the molecule is balanced by the restoring force.

III. The non–polar molecule develops an induced dipole moment.

(a) I and II

(b) II and III

(c) I and III

(d) I, II and III

Answer: D

Question: A conductor carries a certain charge. When it is connected to another uncharged conductor of finite capacity, then the energy of the combined system is

(a) more than that of the first conductor

(b) less than that of the first conductor

(c) equal to that of the first conductor

(d) uncertain

Answer: B

Question: A positively charged particle is released from rest in an uniform electric field. The electric potential energy of the charge

(a) remains a constant because the electric field is uniform

(b) increases because the charge moves along the electric field

(c) decreases because the charge moves along the electric field

(d) decreases because the charge moves opposite to the electric field 

Answer: C

Question: A capacitor is charged by a battery. The battery is removed and another identical uncharged capacitor is connected in parallel. The total electrostatic energy of resulting system

(a) decreases by a factor of 2

(b) remains the same

(c) increases by a factor of 2

(d) increases by a factor of 4

Answer: A

Question:  Choose the correct option

Assertion : For a non-uniformly charged thin circular ring with net charge is zero, the electric field at any point on axis of the ring is zero.

Reason : For a non-uniformly charged thin circular ring with net charge zero, the electric potential at each point on axis of the ring is zero.

(a) Assertion is correct, reason is correct; reason is a correct explanation for assertion.

(b) Assertion is correct, reason is correct; reason is not a correct explanation for assertion

(c) Assertion is correct, reason is incorrect

(d) Assertion is incorrect, reason is correct.

Answer: D

Question: Which of the following about potential at a point due to a given point charge is true ?

The potential at a point P due to a given point charge

(a) is a function of distance from the point charge.

(b) varies inversely as the square of distance from the point charge.

(c) is a vector quantity

(d) is directly proportional to the square of distance from the point charge.

Answer: A

Question: There are two metallic spheres of same radii but one is solid and the other is hollow, then

(a) solid sphere can be given more charge

(b) hollow sphere can be given more charge

(c) they can be charged equally (maximum)

(d) None of the above

Answer: C

Question: The potential energy of a system of two charges is negative when

(a) both the charges are positive

(b) both the charges are negative

(c) one charge is positive and other is negative

(d) both the charges are separated by infinite distance

Answer: C

Question: A charge is brought from a point on the equatorial plane of a dipole to its mid-point. Which of the following quantities remains constant ?

(a) Electric field

(b) Force on the charge brought.

(c) Torque exerted by the charge on dipole.

(d) Electric potential

Answer: D

Question: In a charged capacitor, the energy is stored in

(a) the negative charges

(b) the positive charges

(c) the field between the plates

(d) both (a) and (b)

Answer: C

Question: A conductor carries a certain charge. When it is connected to another uncharged conductor of finite capacity, then the energy of the combined system is

(a) more than that of the first conductor

(b) less than that of the first conductor

(c) equal to that of the first conductor

(d) uncertain

Answer: B

Question: Capacity of a parallel plate condenser can be increased by

(a) increasing the distance between the plates

(b) increasing the thickness of the plates

(c) decreasing the thickness of the plates

(d) decreasing the distance between the plates

Answer: D

Question: Van de Graaff generator is used to

(a) store electrical energy

(b) build up high voltage of few million volts

(c) decelerate charged particle like electrons

(d) both (a) and (b)

Answer: B

Question: Consider the following statements and select the correct statement(s).

I. Electric field lines are always perpendicular to equipotential surface.

II. No two equipotential surfaces can intersect each other.

III. Electric field lines are in the direction of tangent to an equipotential surface.

(a) I only

(b) II only

(c) I and II

(d) I, II and III

Answer: C

Question: The electric potential inside a conducting sphere

(a) increases from centre to surface

(b) decreases from centre to surface

(c) remains constant from centre to surface

(d) is zero at every point inside

Answer: C

Question: A cube of a metal is given a positive charge Question: For this system, which of the following statements is true?

(a) Electric potential at the surface of the cube is zero

(b) Electric potential within the cube is zero

(c) Electric field is normal to the surface of the cube

(d) Electric field varies within the cube

Answer: D

Question: If a unit positive charge is taken from one point to another over an equipotential surface, then

(a) work is done on the charge

(b) work is done by the charge

(c) work done is constant

(d) no work is done

Answer: D

Question: The potential energy of a system of two charges is negative when

(a) both the charges are positive

(b) both the charges are negative

(c) one charge is positive and other is negative

(d) both the charges are separated by infinite distance

Answer: C

Question: Consider the followoing statements regarding series grouping of capacitors and select the correct statements.

I. Charge on each capacitor remains same and equals to the main charge supplied by the battery.

II. Potential difference and energy distributes in the reverse ratio of capacitance.

III. Effective capacitance is even les than the least of teh individual capacitances.

(a) I and II

(b) I and III

(c) II and III

 (d) I, II and III

Answer: D

Question: Energy is stored in a capacitor in the form of

(a) electrostatic energy

(b) magnetic energy

(c) light energy

(d) heat energy

Answer: A

Question: The potential gradient at which the dielectric of a condenser just gets punctured is called

(a) dielectric constant

(b) dielectric strength

(c) dielectric resistance

(d) dielectric number

Answer: B

Question: Capacitiors are used in electrical circuits where appliances need more

(a) voltage

(b) current

(c) resistance

(d) power

Answer: B

Question: ...X... is a machine that can build up high voltages of the order of a few million volts. Here, A refers to

(a) Dynamo

(b) Van De Graaff generator

(c) DC generator

(d) AC generator

Answer: B

Question: Consider the following statements and select the correct option

I. In an external electric field, the positive and negative charges of a non–polar molecule are displaced in opposite directions.

II. In non –polar molecules displacement stops when the external force on the constituent charges of the molecule is balanced by the restoring force.

III. The non–polar molecule develops an induced dipole moment.

(a) I and II

(b) II and III

(c) I and III

(d) I, II and III

Answer: D

Question: The electric potential inside a conducting sphere

(a) increases from centre to surface

(b) decreases from centre to surface

(c) remains constant from centre to surface

(d) is zero at every point inside

Answer: C

Question: A cube of a metal is given a positive charge Question: For this system, which of the following statements is true?

(a) Electric potential at the surface of the cube is zero

(b) Electric potential within the cube is zero

(c) Electric field is normal to the surface of the cube

(d) Electric field varies within the cube

Answer: D

Question: From a point charge, there is a fixed point A. At A, there is an electric field of 500 V/m and potential difference of 3000 V. Distance between point charge and A will be

(a) 6 m

(b) 12 m

(c) 16 m

(d) 24 m

Answer: A

Question: Consider the following statements and select the correct statement(s).

I. Electric field lines are always perpendicular to equipotential surface.

II. No two equipotential surfaces can intersect each other.

III. Electric field lines are in the direction of tangent to an equipotential surface.

(a) I only   

(b) II only

(c) I and II

(d) I, II and III

Answer: A

Question: The electrostatic force between the metal plates of an isolated parallel plate capacitor C having a charge Q and area A, is

(a) independent of the distance between the plates

(b) linearly proportional to the distance between the plates

(c) inversely proportional to the distance between theplates

(d) proportional to the square root of the distance betweenthe plates

Answer: A

Question: A cube of a metal is given a positive charge Question: For this system, which of the following statements is true?

(a) Electric potential at the surface of the cube is zero

(b) Electric potential within the cube is zero

(c) Electric field is normal to the surface of the cube

(d) Electric field varies within the cube

Answer: D

Question: If a unit positive charge is taken from one point to another over an equipotential surface, then

(a) work is done on the charge

(b) work is done by the charge

(c) work done is constant

(d) no work is done

Answer: D

Question: The electric potential at a point on the equatorial line of an electric dipole is

(a) directly proportional to distance

(b) inversely proportional to distance

(c) inversely proportional to square of the distance

(d) None of these

Answer: D

Question: Energy is stored in a capacitor in the form of

(a) electrostatic energy

(b) magnetic energy

(c) light energy

(d) heat energy

Answer: A

Question: A parallel plate condenser is immersed in an oil of dielectric constant 2. The field between the plates is

(a) increased, proportional to 2

(b) decreased, proportional to 1/2 

(c) increased, proportional to – 2

(d) decreased, proportional to -1/2

Answer: B

Question: In a charged capacitor, the energy resides

(a) in the positive charges.

(b) in both the positive and negative charges.

(c) in the field between the plates.

(d) around the edges of the capacitor plates.

Answer: C

Question: Which of the following about potential difference between any two points is true?

I. It depends only on the initial and final position.

II. It is the work done per unit positive charge in moving from one point to other.

III. It is more for a positive charge of two units as compared to a positive charge of one unit.

(a) I only

(b) II only

(c) I and II

(d) I, II and III

Answer: C

Question: In a region of constant potential

(a) the electric field is uniform

(b) the electric field is zero

(c) the electric field shall necessarily change if a charge is placed outside the region

(d) None of these

Answer: B

Question: A unit charge moves on an equipotential surface from a point A to point B, then

(a) VA – VB = + ve

(b) VA – VB = 0

(c) VA – VB = – ve

(d) it is stationary

Answer: B

Question: There are two metallic spheres of same radii but one is solid and the other is hollow, then

(a) solid sphere can be given more charge

(b) hollow sphere can be given more charge

(c) they can be charged equally (maximum)

(d) None of the above

Answer: C

Question: The electric potential at a point on the equatorial line of an electric dipole is

(a) directly proportional to distance

(b) inversely proportional to distance

(c) inversely proportional to square of the distance

(d) None of these

Answer: D

Question: A capacitor works in

(a) A. C. circuits

(b) D. C. circuits

(c) both (a) and (b)

(d) neither (a) nor (b)

Answer: D

Question: A parallel plate condenser is immersed in an oil of dielectric constant 2. The field between the plates is

(a) increased, proportional to 2

(b) decreased, proportional to 1/2 

(c) increased, proportional to – 2

(d) decreased, proportional to -1/2

Answer: B

Question: In a charged capacitor, the energy resides

(a) in the positive charges.

(b) in both the positive and negative charges.

(c) in the field between the plates.

(d) around the edges of the capacitor plates.

Answer: C

Question: Consider the following statements and select the correct statement(s).

I. Electric field lines are always perpendicular to equipotential surface.

II. No two equipotential surfaces can intersect each other.

III. Electric field lines are in the direction of tangent to an equipotential surface.

(a) I only

(b) II only

(c) I and II

(d) I, II and III

Answer: C

Question: Which of the following about potential at a point due to a given point charge is true ?

The potential at a point P due to a given point charge

(a) is a function of distance from the point charge.

(b) varies inversely as the square of distance from the point charge.

(c) is a vector quantity.

(d) is directly proportional to the square of distance from the point charge.

Answer: A

Question: Choose the correct option

Assertion : Electric field is discontinuous across the surface of a spherical charged shell.

Reason : Electric potential is continuous across the surface of a spherical charged shell

(a) Assertion is correct, reason is correct; reason is a correct explanation for assertion.

(b) Assertion is correct, reason is correct; reason is not a correct explanation for assertion

(c) Assertion is correct, reason is incorrect

(d) Assertion is incorrect, reason is correct.

Answer: B

Question: Equipotentials at a great distance from a collection of charges whose total sum is not zero are approximately

(a) spheres       

(b) planes

(c) paraboloids

(d) ellipsoids

Answer: A

Question:  The diagrams below show regions of equipotentials

(a) In all the four cases the work done is the same

(b) Minimum work is required to move q in figure (i)

(c) Maximum work is required to move q in figure (ii)

(d) Maximum work is required to move q in figure (iii)

Answer: A

Question: A unit charge moves on an equipotential surface from a point A to point B, then

(a) VA – VB = + ve

(b) VA – VB = 0

(c) VA – VB = – ve

(d) it is stationary

Answer: B

Question: The maximum electric field that a dielectric medium can withstand without break-down is called its

(a) permittivity

(b) dielectric constant

(c) electric susceptibility

(d) dielectric strength

Answer: D

Question: A sheet of aluminium foil of negligible thickness is introduced between the plates of a capacitor. The capacitance of the capacitor

(a) decreases

(b) remains unchanged

(c) becomes infinite

(d) increases

Answer: B

Question: The work done in placing a charge of 8 × 10^–18 coulomb on a condenser of capacity 100 micro-farad is

(a) 3.1 × 10^–26 joule

(b) 4 × 10^–10 joule

(c) 32 × 10^–32 joule

(d) 16 × 10^–232 joule

Answer: C

Question: Which of the following is / are true about the principle of Van de Graaff generator?

(a) The action of sharp points.

(b) The charge given to a hollow conductor is tranferred to outer surface and is distributed uniformly over it.

(c) It is used for accelerating uncharged particle.

(d) Both (a) and (b)

Answer: D

Question: It becomes possible to define potential at a point in an electric field because electric field

(a) is a conservative field

(b) is a non-conservative field

(c) is a vector field

(d) obeys principle of superposition

Answer: A

Question: To obtain 3 μF capacity from three capacitors of 2 μF each, they will be arranged.

(a) all the three in series

(b) all the three in parallel

(c) two capacitors in series and the third in parallel with the combinatioin of first two

(d) two capacitors in parallel and the third in series with the combinatioin of first two

Answer: C

Question: A hollow metal sphere of radius 5 cm is charged such that the potential on its surface is 10 V. The potential at a distance of 2 cm from the centre of the sphere is

(a) zero

(b) 10 V

(c) 4 V

(d) 10/3 V

Answer: B

Question: A sheet of aluminium foil of negligible thickness is introduced between the plates of a capacitor. The capacitance of the capacitor

(a) decreases

(b) remains unchanged

(c) becomes infinite

(d) increases

Answer: B

Question: An arrangement which consists of two conductors separated by a dielectric medium is called

(a) resistor

(b) inductor

(c) rectifier

(d) capacitor

Answer: D

Question: Van de Graaff generator is used to

(a) store electrical energy

(b) build up high voltage of few million volts

(c) decelerate charged particle like electrons

(d) both (a) and (b)

Answer: B

Question: Which of the following statements is/are correct for equipotential surface ?

I. The potential at all the points on an equipotential surface is same.

II. Equipotential surfaces never intersect each other.

III. Work done in moving a charge from one point to other on an equipotential surface is zero.

(a) I only

(b) II only

(c) I and II

(d) I, II and III

Answer: D

Question: A hollow metal sphere of radius 5 cm is charged such that the potential on its surface is 10 V. The potential at a distance of 2 cm from the centre of the sphere is

(a) zero

(b) 10 V

(c) 4 V

(d) 10/3 V

Answer: B

Question: In a region, the potential is represented by V(x, y, z) = 6x – 8xy – 8y + 6yz, where V is in volts and x, y, z are in metres. The electric force experienced by a charge of 2 coulomb situated at point (1, 1, 1) is :

Answer: D

Question: The electric potential inside a conducting sphere

(a) increases from centre to surface

(b) decreases from centre to surface

(c) remains constant from centre to surface

(d) is zero at every point inside

Answer: C

Question: To obtain 3 μF capacity from three capacitors of 2 μF each, they will be arranged.

(a) all the three in series

(b) all the three in parallel

(c) two capacitors in series and the third in parallel with the combinatioin of first two

(d) two capacitors in parallel and the third in series with the combinatioin of first two

Answer: C

Question: Consider the followoing statements regarding series grouping of capacitors and select the correct statements.

I. Charge on each capacitor remains same and equals to the main charge supplied by the battery.

II. Potential difference and energy distributes in the reverse ratio of capacitance.

III. Effective capacitance is even les than the least of teh individual capacitances.

(a) I and II

(b) I and III

(c) II and III

 (d) I, II and III

Answer: D

Question: The potential gradient at which the dielectric of a condenser just gets punctured is called

(a) dielectric constant

(b) dielectric strength

(c) dielectric resistance

(d) dielectric number

Answer: B

Question: In case of a Van de Graaff generator, the breakdown field of air is

(a) 2 × 108 V m^–1

(b) 3 × 106 V m^–1

(c) 2 × 108 V m^–1

(d) 3 × 104 V m^–1

Answer: B

Question: Which of the following statements is/are correct for equipotential surface ?

I. The potential at all the points on an equipotential surface is same.

II. Equipotential surfaces never intersect each other.

III. Work done in moving a charge from one point to other on an equipotential surface is zero.

(a) I only

(b) II only

(c) I and II

(d) I, II and III

Answer: D

Question: The positive terminal of 12 V battery is connected to the ground. Then the negative terminal will be at

(a) – 6 V

(b) + 12 V

(c) zero

(d) – 12 V

Answer: D

Question: On decreasing the distance between the plates of a parallel plate capacitor, its capacitance

(a) remains unaffected

(b) decreases

(c) first increases then decreases.

(d) increases

Answer: D

Question: Capacity of a parallel plate condenser can be increased by

(a) increasing the distance between the plates

(b) increasing the thickness of the plates

(c) decreasing the thickness of the plates

(d) decreasing the distance between the plates

Answer: D

Question: Which of the following about potential difference between any two points is true?

I. It depends only on the initial and final position.

II. It is the work done per unit positive charge in moving from one point to other.

III. It is more for a positive charge of two units as compared to a positive charge of one unit.

(a) I only

(b) II only

(c) I and II

(d) I, II and III

Answer: C

Question: Two metal pieces having a potential difference of 800 V are 0.02 m apart horizontally. A particle of mass 1.96 × 10^–15 kg is suspended in equilibrium between the plates. If e is the elementary charge, then charge on the particle is

(a) 8

(b) 6

(c) 0.1

(d) 3

Answer: D

Question: The electrostatic potential on the surface of a charged conducting sphere is 100V. Two statements are made in this regard S₁ at any point inside the sphere, electric intensity is zero. S₂ at any point inside the sphere, the electrostatic potential is 100V. Which of the following is a correct statement?

(a) S₁ is true but S₂ is false

(b) Both S₁ and S₂ are false

(c) S₁ is true, S₂ is also true and S₁ is the cause of S₂

(d) S₁ is true, S₂ is also true but the statements are independant

Answer: C

Question: It becomes possible to define potential at a point in an electric field because electric field

(a) is a conservative field

(b) is a non-conservative field

(c) is a vector field

(d) obeys principle of superposition

Answer: A

Question: An electric dipole is kept in non-uniform elecric field. it experiences

(a) a force and a torque

(b) a force but not a torque

(c) a torque but not a force

(d) Neither a force nor a torque

Answer: A

Question: A capacitor works in

(a) A. C. circuits

(b) D. C. circuits

(c) both (a) and (b)

(d) neither (a) nor (b)

Answer: D

Question: ...X... is a machine that can build up high voltages of the order of a few million volts. Here, A refers to

(a) Dynamo

(b) Van De Graaff generator

(c) DC generator

(d) AC generator

Answer: B

Question: Which of the following quantities do not depend on the choice of zero potential or zero potential energy?

(a) Potential at a point

(b) Potential difference between two points

(c) Potential energy of a two-charge system

(d) None of these

Answer: B

Question: A charge is brought from a point on the equatorial plane of a dipole to its mid-point. Which of the following quantities remains constant ?

(a) Electric field

(b) Force on the charge brought.

(c) Torque exerted by the charge on dipole.

(d) Electric potential

Answer: D

Question: The work done in placing a charge of 8 × 10^–18 coulomb on a condenser of capacity 100 micro-farad is

(a) 3.1 × 10^–26 joule

(b) 4 × 10^–10 joule

(c) 32 × 10^–32 joule

(d) 16 × 10^–232 joule

Answer: C

Question:  It becomes possible to define potential at a point in an electric field because electric field

(a) is a conservative field

(b) is a non-conservative field

(c) is a vector field

(d) obeys principle of superposition

Answer: A

Question: Choose the correct option

Assertion : Electric potential and electric potential energy  are different quantities.

Reason : For a system of positive test charge and point charge electric potential energy = electric potential.

(a) Assertion is correct, reason is correct; reason is a correct explanation for assertion.

(b) Assertion is correct, reason is correct; reason is not a correct explanation for assertion

(c) Assertion is correct, reason is incorrect

(d) Assertion is incorrect, reason is correct.

Answer: C

Question: On moving a charge of Q coulomb by X cm, W J of work is done, then the potential difference between the points is

(a) W/Q *V

(b) QW V

(c) Q/W V

(d) Q2 /W V

Answer: A

Question: Capacitiors are used in electrical circuits where appliances need more

(a) voltage

(b) current

(c) resistance

(d) power

Answer: B

Question: Which of the following about potential at a point due to a given point charge is true ?

The potential at a point P due to a given point charge

(a) is a function of distance from the point charge.

(b) varies inversely as the square of distance from the point charge.

(c) is a vector quantity

(d) is directly proportional to the square of distance from the point charge.

Answer: A

Question: In a charged capacitor, the energy is stored in

(a) the negative charges

(b) the positive charges

(c) the field between the plates

(d) both (a) and (b)

Answer: C

Question: Which of the following is / are true about the principle of Van de Graaff generator?

(a) The action of sharp points.

(b) The charge given to a hollow conductor is tranferred to outer surface and is distributed uniformly over it.

(c) It is used for accelerating uncharged particle.

(d) Both (a) and (b)

Answer: D

Question:  A long, hollow conducting cylinder is kept coaxially inside another long, hollow conducting cylinder of larger radius. Both the cylinders are initially electrically neutral

(a) A potential difference appears between the two cylinders when a charge density is given to the inner cylinder.

(b) A potential difference appears between two cylinders when a charge density is given to the outer cylinder.

(c) No potential difference appears between the two cylinders when a uniform line charge is kept along the axis of the cylinders.

(d) No potential difference appears between the two cylinders when same charge density is given to both the cylinders.

Answer: A

Question: On decreasing the distance between the plates of a parallel plate capacitor, its capacitance

(a) remains unaffected

(b) decreases

(c) first increases then decreases.

(d) increases

Answer: D

Question: When a metal plate is introduced between the two plates of a charged capacitor and insulated from them, then which of following statement(s) is/are correct ?

I. The metal plate divides the capacitor into two capacitors connected in parallel to each other

II. The metal plate divides the capacitors into two capacitors connected in series with each other

III. The metal plate is equivalent to a dielectric of zero dielectric constant

(a) I only

(b) II only

(c) I and II

(d) I, II and III

Answer: B

Question: An electric dipole is kept in non-uniform elecric field. it experiences

(a) a force and a torque

(b) a force but not a torque

(c) a torque but not a force

(d) Neither a force nor a torque

Answer: A

Question: When a metal plate is introduced between the two plates of a charged capacitor and insulated from them, then which of following statement(s) is/are correct ?

I. The metal plate divides the capacitor into two capacitors connected in parallel to each other

II. The metal plate divides the capacitors into two capacitors connected in series with each other

III. The metal plate is equivalent to a dielectric of zero dielectric constant

(a) I only

(b) II only

(c) I and II

(d) I, II and III

Answer: B

Question: Which of the following quantities do not depend on the choice of zero potential or zero potential energy?

(a) Potential at a point

(b) Potential difference between two points

(c) Potential energy of a two-charge system

(d) None of these

Answer: B

Question: An arrangement which consists of two conductors separated by a dielectric medium is called

(a) resistor

(b) inductor

(c) rectifier

(d) capacitor

Answer: D

Question: The maximum electric field that a dielectric medium can withstand without break-down is called its

(a) permittivity

(b) dielectric constant

(c) electric susceptibility

(d) dielectric strength

Answer: D

Question:  Which of the following quantities do not depend on the choice of zero potential or zero potential energy?

(a) Potential at a point

(b) Potential difference between two points

(c) Potential energy of a two-charge system

(d) None of these

Answer: B

Question: In a region of constant potential

(a) the electric field is uniform

(b) the electric field is zero

(c) the electric field shall necessarily change if a charge is placed outside the region

(d) None of these

Answer: B

Question: When air in a capacitor is replaced by a medium of dielectric constant K, the capacity

(a) decreases K times

(b) increases K times

(c) increases K2 times

(d) remains constant

Answer: B

Question: When air in a capacitor is replaced by a medium of dielectric constant K, the capacity

(a) decreases K times

(b) increases K times

(c) increases K2 times

(d) remains constant

Answer: B

Question: The electric potential at a point on the equatorial line of an electric dipole is

(a) directly proportional to distance

(b) inversely proportional to distance

(c) inversely proportional to square of the distance

(d) None of these

Answer: D

Question: The positive terminal of 12 V battery is connected to the ground. Then the negative terminal will be at

(a) – 6 V

(b) + 12 V

(c) zero

(d) – 12 V

Answer: D

Question: An equipotential surface is that surface

(a) on which each and every point has the same potential

(b) which has negative potential

(c) which has positive potential

(d) which has zero potential

Answer: A

Question: In case of a Van de Graaff generator, the breakdown field of air is

(a) 2 × 108 V m^–1

(b) 3 × 106 V m^–1

(c) 2 × 108 V m^–1

(d) 3 × 104 V m^–1

Answer: B

Question: An equipotential surface is that surface

(a) on which each and every point has the same potential

(b) which has negative potential

(c) which has positive potential

(d) which has zero potential

Answer: A

Question: On moving a charge of Q coulomb by X cm, W J of work is done, then the potential difference between the points is

(a) W/Q *V

(b) QW V

(c) Q/W V

(d) Q2 /W V

Answer: A