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Electrostatic Potential and Capacitance MCQ Class 12 Physics

Please refer to Chapter 2 Electrostatic Potential and Capacitance MCQ Class 12 Physics with answers below. These multiple-choice questions have been prepared based on the latest NCERT book for Class 12 Physics. Students should refer to MCQ Questions for Class 12 Physics with Answers to score more marks in Grade 12 Physics exams. Students should read the chapter Electrostatic Potential and Capacitance and then attempt the following objective questions.

MCQ Questions Class 12 Physics Chapter 2 Electrostatic Potential and Capacitance

The Electrostatic Potential and Capacitance MCQ Class 12 Physics provided below covers all important topics given in this chapter. These MCQs will help you to properly prepare for exams.

Question. Consider a uniform electric field in the z-direction. The potential is a constant
(a) for any x for a given z
(b) for any y for a given z
(c) on the x-y plane for a given z
(d) all of these

D

Question. A test charge is moved from lower potential point to a higher potential point. The potential energy of test charge will
(a) remain the same
(b) increase
(c) decrease
(d) become zero

C

Question. Dielectric constant for a metal is
(a) zero
(b) infinite
(c) 1
(d) 10

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

A

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.

D

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) increases by a factor of 4.
(b) decreases by a factor of 2.
(c) remains the same.
(d) increases by a factor of 2.

B

Question. Which of the following options is correct? In a region of constant potential
(a) the electric field is uniform.
(b) the electric field is zero.
(c) there can be charge inside the regiofi.
(d) the electric field shall necessarily change if a charge is placed outside the region.

B

Question. Which of the following statement is true?
(a) Electrostatic force is a conservative force.
(b) Potential at a point is the work done per unit charge in bringing a charge from any point to infinity.
(c) Electrostatic force is non-conservative
(d) Potential is the product of charge and work.

A

Question. In a region of constant potential
(a) the electric field is uniform.
(b) the electric field is zero.
(c) there can be no charge inside the region.
(d) both (b) and (c) are correct.

D

Question. Which of the following statements is false for a perfect conductor?
(a) The surface of the conductor is an equipoten-tial surface.
(b) The electric field just outside the surface of a conductor is perpendicular to the surface.
(c) The charge carried by a conductor is always uniformly distributed over the surface of the conductor.
(d) None of these.

D

Question. Two identical capacitors are joined in parallel, charged to a potential V, separated and then connected in series, the positive plate of one is connected to the negative of the other. Which of the following is true?
(a) The charges on the free plated connected to-gether are destroyed.
(b) The energy stored in ths system increases.
(c) The potential difference between the free plates is 2V.
(d) The potential difference remains constant.

C

Question. Equipotential surfaces
(a) are closer in regions of large electric fields compared to regions of lower electric fields.
(b) will be more crowded near sharp edges of a conductor.
(c) will always be equally spaced.
(d) both (i) and (ii) are correct.

D

Question. Which of the following statement is true?
(a) Electrostatic force is a conservative force.
(b) Potential at a point is the work done per unit charge in bringing a charge from any point to infinity.
(c) Electrostatic force is non-conservative
(d) Potential is the productof charge and work.

A

Question. In a region of constant potential
(a) the electric field is uniform.
(b) the electric field is zero.
(c) there can be no charge inside the region.
(d) both (ii) and (iii) are correct.

D

Question. In a region of constant potential
(a) the electric field is uniform
(b) the electric field is zero
(c) there can be charge inside the region.
(d) the electric field shall necessarily change if a charge is placed outside the region.

B

Question. In a parallel plate capacitor, the capacity increases if
(a) area of the plate is decreased.
(b) distance between the plates increases.
(c) area of the plate is increased.
(d) dielectric constantly decreases.

C

Question. Consider a uniform electric field in the z direction. The potential is not a constant
(a) in all space.
(b) for any x for a given z.
(c) for any y for a given z.
(d) on the x-y plane for a given z.

A

Question. For equipotential surfaces, which statement is not correct?
(a) are closer in regions of large electric fields compared to regions of lower electric fields.
(b) will always be equally spaced.
(c) will be more crowded near sharp edges of a conductor.
(d) will be more crowded near regions of large charge densities.

B

Question. Three different capacitors are connected in series. Then:
(a) They will have equal charges
(b) They will have same potential
(c) Both 1 & 2
(d) None of these

A

Question. A hollow metal sphere of radius 10 cm is charged such that the potential on its surface is 80 volt. The potential at the centre of the sphere is:
(a) 8 volt
(b) 800 volt
(c) 80 volt
(d) Zero

C

Question. Consider a uniform electric field in the z direction. The potential is a constant
(a) For any x for a given z
(b) For any y for a given z
(c) On the x-y plane for a given z
(d) All of these

D

Question. When two capacitors charged to different potentials are connected by connecting wire, what is not true?
(a) Charge lost by one is equal to charge gained by the other
(b) Potential lost by one is equal to potential gained by the other
(c) Some energy is lost
(d) Both the capacitors acquire a common potential

B

Question. If the distance between the plates of capacitor is increased, then capacitance:
(a) Increases
(b) Decreases
(c) Remains the same
(d) First increases then decreases

B

Question. Equipotential surfaces
(a) Are closer in regions of larger electric fields compared to regions of lower electric field
(b) Will be more crowded near sharp edges of a conductor
(c) Will always be equally spaced
(d) Both A and B are correct

D

Question. When air is replaced by a dielectric constant K, the maximum force of attraction between two charges separated by a distance
(a) Increases by K times
(b) Remains Unchanged
(c) Decreases by K times
(d) Increases by 2K times

C

Question. A parallel plate capacitor is maintained at a certain potential difference. When a 3 mm thick slab is introduced amid the plates, in order to maintain the same potential difference, the distance between the plates is enlarged by 2.4 mm. Find the dielectric constant of the slab.
(a) 4
(b) 3
(c) 5
(d) Information incomplete

C

Question. Which of the following is false for a perfect conductor?
(a) The surface of conductor is an equipotential surface
(b) The electric field just outside the surface of conductor is perpendicular to the surface
(c) The charge carried by a metallic sphere is always uniformly distributed over its surface
(d) None of these

D

Question. Electric field is always
(a) Parallel to equipotential surface
(b) Perpendicular to equipotential surface
(c) It can be perpendicular and parallel as well
(d) It does not depend on distribution of charge

B

Question. If a conductor has potential V ≠ 0 and there are no charge anywhere else outside
(a) There must be charges on the surface or inside itself
(b) There cannot be any charge in the body of conductor
(c) There must be charges only on surface
(d) Both A and B are correct

D

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.

A

Question. A spherical conductor is charged. The electric field intensity at its centre will be
(a) infinite
(b) zero
(c)) equal to that at the surface
(d) None of these

B

Question. A hollow metallic sphere of radius 5 cm is charged to 10 volt. The potential at centre is,
(a) zero
(b) 10 volt
(c) The same as on 5 cm distance
(d) none

B

Question. The capacity of a conductor is inversely proportional to
(a) area of plates
(b) permittivity of medium between plates
(c) distance between plates
(d) None of these

B

Question. If an earthed conductor is brought near an insulated conductor, then the capacity of insulated conductor
(a) decreases
(b) increases
(c) remain unchanged
(d) none

B

Question. Two capacitors, each of capacitance C, are connected in series. Their equivalent capacitance is
(a) 2C
(b) C
(c) C / 2
(d) 1 / 2C

C

Question. The value of dielectric constant of a substance except air is always greater than
(a) zero
(b) 0.5
(c) 1
(d) 2

C

Question. The electric potential due to a small electric dipole at a large distance r from the center of the dipole is proportional to
(a) r
(b) 1 / r
(c) 1 / r2
(d) 1 / r3

C

Question. If a charge moves in an electrical field
(a) energy is lost
(b) energy is gained
(c) energy is conserved
(d) energy is unchanged

C

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) increased proportional to √2
(c) decreased proportional to 1/2
(d) decreased proportional to1/√2

C

Question. The electric field between the plates of a fully charged capacitor is E. If a material of dielectric constant k is introduced between the plates, the electric field at a point between the plates
(a) decreases
(b) increases
(c) becomes E/k
(d) remains unchanged

C

Question. Equipotential surface associated with an electric field, which is increasing in magnitude along the X-direction, are
(a) planes parallel to YZ-plane.
(b) planes parallel to XZ-plane.
(c) planes parallel to XY-plane.
(d) coaxial cylinder of increasing radii around the X-axis.

A

Question. What is angle between electric field and equipotential surface?
(a) 90° always
(b) 0° always
(c) 0° to 90°
(d) 0° to 180°

A

Question. Two capacitors of capacitances 3 mF and 6 mF are charged to a potential of 12 V each. They are now connected to each other, with the positive plate of each joined to the negative plate of the other. The potential difference across 3 mF will be
(a) 3 V
(b) zero
(c) 6 V
(d) 4 V

D

Question. The plates of a parallel plate capacitor are 4 cm apart, the first plate is at 300 V and the second plate at – 100 V. The voltage at 3 cm from the second plate is
(a) 200 V
(b) 400 V
(c) 250 V
(d) 500 V

A

Question. Find the dipole moment of a system where the potential 2.0 × 10–5 V at a point P, 0.1m from the dipole is 3.0 × 104. (Use q = 30°).
(a) 2.57 × 10–17 Cm
(b) 1.285 × 10–15 Cm
(c) 1.285 × 10–17 Cm
(d) 2.57 × 10–15 Cm

A

Question. A battery of e.m.f. V volt, resistors R1 and R2, a condenser C and switches S1 and S2 are connected in a circuit shown. The condenser will get fully charged to V volt when
(a) S1 and S2 are both closed
(b) S1 and S2 are both open
(c) S1 is open and S2 is closed
(d) S1 is closed and S2 is open

D

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

A

Question. Three charges 2 q, – q and – q are located at the vertices of an equilateral triangle. At the centre of the triangle
(a) the field is zero but potential is non-zero
(b) the field is non-zero, but potential is zero
(c) both field and potential are zero
(d) both field and potential are non-zero

B

Question. Two conducting spheres of radii r1 and r2 are equally charged. The ratio of their potentials is
(a) r1 / r2
(b) r2 / r1
(c) r12 / r22
(d) r22 / r12

B

Question. Four capacitors, each 50 μF are connected as shown. The DC voltmeter V reads 100 V. The charge on each plate of each capacitor is

(a) 2 × 10–3 C
(b) 5 × 10–3 C
(c) 0.2 C
(d) 0.5 C