CBSE Class 12 Physics Electrostatic Potential And Capacitance Worksheet Set C

Question. The ratio of charge to potential of a body is known as
(a) capacitance
(b) inductance
(c) conductance
(d) resistance

Answer: A

Question. On moving a charge of 20 C by 2 cm, 2 J of work is done. Then the potential difference between the points is
(a) 0.1 V
(b) 8 V
(c) 2 V
(d) 0.5 V

Answer: A

Question. In brining an electron towards another electron, the electrostatic potential energy of the system
(a) increases
(b) decreases
(c) remains unchanged
(d) becomes zero

Answer: A

Question. Electric potential of earth is taken to be zero, because earth is a good
(a) insulator
(b) conductor
(c) semi-conductor
(d) dielectric

Answer: B

Question. Some charge is being given to a conductor. Then, its potential
(a) is maximum at surface.
(b) is maximum at centre.
(c) remains the same throughout the conductor.
(d) is maximum somewhere between surface and centre.

Answer: 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.

Answer: 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°

Answer: A

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. The electrostatic potential on the surface of a charged conducting sphere is 100 V. 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 100 V.
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 independent.

Answer: C

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. 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 be more crowded near regions of large charge densities.
(d) All of the options

Answer: D

Question. A 2 mF capacitor is charged to 200 volt and then the battery is disconnected. When it is connected in parallel to another uncharged capacitor, the potential difference between the plates of both is 40 volt. The capacitance of the other capacitor is
(a) 2 mF
(b) 4 mF
(c) 8 mF
(d) 16 mF

Answer: C

Question. Two identical metal plates, separated by a distance d form a parallel-plate capacitor. A metal sheet of thickness d/2 is inserted between the plates. The ratio of the capacitance after the insertion of the sheet to that before insertion is
(a) 2 :1
(b) 2 : 1
(c) 1 : 1
(d) 1 : 2

Answer: B

Question. n identical capacitors joined in parallel are charged to a common potential V. The battery is disconnected. Now, the capacitors are separated and joined in series. For the new combination:
(a) energy and potential difference both will remain unchanged
(b) energy will remain same, potential difference will become nV
(c) energy and potential both will become n times
(d) energy will become n times, potential difference will remain V.

Answer: B

Question. The capacitance of a capacitor becomes 7/6 times its original value if a dielectric slab of thickness t = (2/3) d is introduced in between the plates, where d is the separation between the plates. The dielectric constant of the slab is
(a) 14/11
(b) 11/14
(c) 7/11
(d) 11/7

Answer: 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

Answer: 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

Answer: A

Question. Three capacitors of capacitance 1mF, 2 mF and 3 mF are connected in series and a p.d. of 11 V is applied across the combination. Then, the p.d. across the plates of 1 mF capacitor is
(a) 2 V
(b) 4 V
(c) 1 V
(d) 6 V

Answer: D

Question. A conducting sphere of radius R is given a charge Q. The electric potential and the electric field at the centre of the sphere respectively are
(a) zero and Q/4π∈₀R²
(b) Q/4π∈₀R and zero
(c) Q/π∈₀R and Q/4π∈₀R²
(d) both are zero

Answer: B

Question. Four point charges – Q, – q, 2q and 2Q are placed, one at each corner of the square. The relation between Q and q for which the potential at the centre of the square is zero is
(a) Q = (1/2)q
(b) Q = – q
(c) Q = – (1/2)q
(d) Q = q

Answer: B

Fill in the Blanks

Question. The magnitude of electric field is given by the change in the magnitude of potential per unit __________ normal to the equipotential surface at the point.
Answer: displacement

Question. For linear isotropic dielectrics, P =  X_eE who X_e is a constant characteristic of the dielectric and is known as the __________ of the dielectric medium.
Answer: susceptibility

Question. The potential energy of two like charged (q1q2 > 0) is __________.
Answer: positive

Question. The potential energy of two unlike charges (q1q2 < 0) is __________.
Answer: negative

Question. The maximum electric field that a dielectric medium can withstand without break-down of its insulting property is called its __________.
Answer: dielectric strength

Question. The dielectric constant of a substance is a factor (>1) by which the capacitance __________ from its vacuum value, when the dielectric is inserted fully between the plates of a capacitor.
Answer: increases

Question. It is safer to be inside the car rather than standing outside under a tree during lightening is based on __________ concept.
Answer: electrostatic shielding

Question. Equipotential surfaces due to long linear change distribution will be __________ in shape.
Answer: cylindrical

Question. Two capacitors each of capacitance 2 mF are connected in series. Equivalent capacitance will be ___________.
Answer: 1 mF

Question. Electric field is in the direction in which the potential ___________ steepest.
Answer: decreases

Please click on below link to download CBSE Class 12 Physics Electrostatic Potential And Capacitance Worksheet Set C