Question 1

Five identical 3.5 mF capacitors are connected together electrically.What is the least possible capacitance of the combination?

Accepted Answer

A)  0.58 mF 
B)  0.88 mF 
C)  0.70 mF 
D)  7 mF 
E)  ​0.57 mF 
A)  0.58 mF 
B)  0.88 mF 
C)  0.70 mF 
D)  7 mF 
E)  ​0.57 mF

Question 2

When charge Q1 is placed at point P1,the resulting potential at point P is V1.When Q2 is placed at point P2 after Q1 is in position at P1,the resulting potential at P becomes V2.What is the potential at point P if charge Q1 is then removed?

Accepted Answer

A)  V1 + V2 
B)  V1 - V2 
C)  V2 - V1 
D)  (V1 + V2)/2 
A)  V1 + V2 
B)  V1 - V2 
C)  V2 - V1 
D)  (V1 + V2)/2

Question 3

If C = 42 µF,determine the equivalent capacitance for the combination shown.

Accepted Answer

A)  42 µF 
B)  24 µF 
C)  12 µF 
D)  28 µF 
E)  33​ µF 
A)  42 µF 
B)  24 µF 
C)  12 µF 
D)  28 µF 
E)  33​ µF

Question 4

A 0.25-μF capacitor is connected to a 300-V battery.What potential energy is stored in the capacitor?

Accepted Answer

A)  1.2 × 10−3 J 
B)  3.8 × 10−4 J 
C)  2.25 J 
D)  0.011 J 
E)  ​0.023 J 
A)  1.2 × 10−3 J 
B)  3.8 × 10−4 J 
C)  2.25 J 
D)  0.011 J 
E)  ​0.023 J

Question 5

Doubling the voltage across a parallel plate capacitor does not double which of the following?

Accepted Answer

A)  the charge 
B)  the electric field between the plates 
C)  the energy stored 
D)  both a and b 
A)  the charge 
B)  the electric field between the plates 
C)  the energy stored 
D)  both a and b

Question 6

A parallel-plate capacitor has a capacitance of 24 µF.What potential difference across the plates is required to store 6.8 × 10−4 C on this capacitor?

Accepted Answer

A)  28.3 V 
B)  28.3 × 10-2 V 
C)  39.2 × 10−8 V 
D)  32.6 V 
E)  32.6​× 10−8 V 
A)  28.3 V 
B)  28.3 × 10-2 V 
C)  39.2 × 10−8 V 
D)  32.6 V 
E)  32.6​× 10−8 V

Question 7

An electron is released from rest at the negative plate of a parallel-plate capacitor.If the distance across the plate is 6.0 mm and the potential difference across the plate is 4.0 V,with what velocity does the electron hit the positive plate? (me = 9.1 × 10−31 kg,e = 1.6 × 10−19 C)

Accepted Answer

A)  1.4 × 105 m/s 
B)  1.7 × 106 m/s 
C)  2.4 × 106 m/s 
D)  1.2 × 106 m/s 
E)  1.2 × 105 m/s 
A)  1.4 × 105 m/s 
B)  1.7 × 106 m/s 
C)  2.4 × 106 m/s 
D)  1.2 × 106 m/s 
E)  1.2 × 105 m/s

Question 8

In which case does an electric field do positive work on a charged particle?

Accepted Answer

A)  A negative charge moves opposite to the direction of the electric field. 
B)  A positive charge is moved to a point of higher potential energy. 
C)  A positive charge completes one circular path around a stationary positive charge. 
D)  A positive charge completes one elliptical path around a stationary positive charge. 
A)  A negative charge moves opposite to the direction of the electric field. 
B)  A positive charge is moved to a point of higher potential energy. 
C)  A positive charge completes one circular path around a stationary positive charge. 
D)  A positive charge completes one elliptical path around a stationary positive charge.

Question 9

A 0.55-μF capacitor is connected to a 310-V battery.Find the charge on the capacitor.

Accepted Answer

A)  1.7 × 10−12 C 
B)  5.6 × 10−4 C 
C)  1.8 C 
D)  9.6 10−12 C 
E)  ​1.7 × 10−4 C 
A)  1.7 × 10−12 C 
B)  5.6 × 10−4 C 
C)  1.8 C 
D)  9.6 10−12 C 
E)  ​1.7 × 10−4 C

Question 10

The unit of electrical potential,the volt,is dimensionally equivalent to:

Accepted Answer

A)  J⋅C. 
B)  J/C. 
C)  C/J. 
D)  F⋅C. 
A)  J⋅C. 
B)  J/C. 
C)  C/J. 
D)  F⋅C.

Question 11

A parallel-plate capacitor with plate area A and plate separation d has a capacitance of 3.0  
With the gap between the plates unfilled.The gap is then filled with two dielectric materials,one with dielectric constant 2.0 and the other one with dielectric constant 4.0.Each slab of dielectric has area A/2 and thickness d,the placing side-by-side of the dielectics resulting in the gap being completely filled.Which of the following combinations of capacitors will have the same capacitance as the newly filled parallel-plate one?
​

Accepted Answer

A)  a 4.5-
  capacitor and a 9-
  capacitor in parallel 
B)  a 4.5-
  capacitor and a 9-
  capacitor in series 
C)  a 9-
  capacitor and a 18-
  capacitor in parallel 
D)  a 9-
  capacitor and a 18-
  capacitor in series 
E)  ​a 4.5-
  capacitor and a 18-
  capacitor in parallel 
A)  a 4.5-
  capacitor and a 9-
  capacitor in parallel 
B)  a 4.5-
  capacitor and a 9-
  capacitor in series 
C)  a 9-
  capacitor and a 18-
  capacitor in parallel 
D)  a 9-
  capacitor and a 18-
  capacitor in series 
E)  ​a 4.5-
  capacitor and a 18-
  capacitor in parallel

Question 12

Six identical 3.5 mF capacitors are connected together electrically.What is the greatest possible capacitance of the combination?

Accepted Answer

A)  0.88 mF 
B)  0.70 mF 
C)  0.58 mF 
D)  21 mF 
E)  ​0.86 mF 
A)  0.88 mF 
B)  0.70 mF 
C)  0.58 mF 
D)  21 mF 
E)  ​0.86 mF

Question 13

Inserting a dielectric material between two charged parallel conducting plates,originally separated by air and disconnected from a battery,will produce what effect on the capacitor?

Accepted Answer

A)  increase charge 
B)  increase voltage 
C)  increase capacitance 
D)  decrease capacitance 
A)  increase charge 
B)  increase voltage 
C)  increase capacitance 
D)  decrease capacitance

Question 14

At what distance from a point charge of 7.3 μC would the electrical potential be 4.9 × 104 V? (ke = 8.99 × 109 N⋅m2/C2)

Accepted Answer

A)  1.64 m 
B)  0.4 m 
C)  1.34 m 
D)  6.03 m 
E)  0.67​ m 
A)  1.64 m 
B)  0.4 m 
C)  1.34 m 
D)  6.03 m 
E)  0.67​ m

Question 15

Two point charges of values +3.3 and +5.1 μC,respectively,are separated by 0.65 m.What is the potential energy of this 2-charge system? (ke = 8.99 × 109 N⋅m2/C2)

Accepted Answer

A)  +0.5 J 
B)  −0.2 J 
C)  +0.2 J 
D)  −0.8 J 
E)  ​+0.8 J 
A)  +0.5 J 
B)  −0.2 J 
C)  +0.2 J 
D)  −0.8 J 
E)  ​+0.8 J

Question 16

If C = 14 µF,what is the equivalent capacitance for the combination shown?

Accepted Answer

A)  28 µF 
B)  17 µF 
C)  0.29 µF 
D)  7 µF 
E)  ​672 µF 
A)  28 µF 
B)  17 µF 
C)  0.29 µF 
D)  7 µF 
E)  ​672 µF

Question 17

If a doubly-ionized oxygen atom (O-2)is accelerated from rest by going through a potential difference of 21 V,what will be the change in its kinetic energy?

Accepted Answer

A)  10 eV 
B)  21 eV 
C)  42 eV 
D)  ​33 eV 
E)  ​none of the above 
A)  10 eV 
B)  21 eV 
C)  42 eV 
D)  ​33 eV 
E)  ​none of the above

Question 18

A proton (+1.6 × 10−19 C)moves 15 cm on a path in the direction of a uniform electric field of strength 2.6 N/C.How much work is done on the proton by the electrical field?

Accepted Answer

A)  6.24 × 10−20 J 
B)  −6.24 × 10−20 J 
C)  16.2 × 10−20 J 
D)  -​6.94 × 10−20 J 
E)  ​zero 
A)  6.24 × 10−20 J 
B)  −6.24 × 10−20 J 
C)  16.2 × 10−20 J 
D)  -​6.94 × 10−20 J 
E)  ​zero

Question 19

An ion is released from rest and moves due to the force from an electric field from a position in the field having a potential of 14 V to a position having a potential of 8 V.The ion:

Accepted Answer

A)  must have a positive charge. 
B)  must have a negative charge. 
C)  can have either a positive or a negative charge. 
D)  must be neutral. 
A)  must have a positive charge. 
B)  must have a negative charge. 
C)  can have either a positive or a negative charge. 
D)  must be neutral.

Question 20

When charges qa,qb,and qc are placed respectively at the corners a,b,and c of a right triangle,the potential at the midpoint of the hypotenuse is 20 V.When the charge qa is removed,the potential at the midpoint becomes 15 V.When,instead,the charge qb is removed (qa and qc both in place),the potential at the midpoint becomes 12 V.What is the potential at the midpoint if only the charge qc is removed from the array of charges?

Accepted Answer

A)  8 V 
B)  5 V 
C)  7 V 
D)  13 V 
A)  8 V 
B)  5 V 
C)  7 V 
D)  13 V

Exam 16: Electrical Energy and Capacitance

Five identical 3.5 mF capacitors are connected together electrically.What is the least possible capacitance of the combination?

When charge Q1 is placed at point P1,the resulting potential at point P is V1.When Q2 is placed at point P2 after Q1 is in position at P1,the resulting potential at P becomes V2.What is the potential at point P if charge Q1 is then removed?

If C = 42 µF,determine the equivalent capacitance for the combination shown.

A 0.25-μF capacitor is connected to a 300-V battery.What potential energy is stored in the capacitor?

Doubling the voltage across a parallel plate capacitor does not double which of the following?

A parallel-plate capacitor has a capacitance of 24 µF.What potential difference across the plates is required to store 6.8 × 10−4 C on this capacitor?

An electron is released from rest at the negative plate of a parallel-plate capacitor.If the distance across the plate is 6.0 mm and the potential difference across the plate is 4.0 V,with what velocity does the electron hit the positive plate? (me = 9.1 × 10−31 kg,e = 1.6 × 10−19 C)

In which case does an electric field do positive work on a charged particle?

A 0.55-μF capacitor is connected to a 310-V battery.Find the charge on the capacitor.

The unit of electrical potential,the volt,is dimensionally equivalent to:

Six identical 3.5 mF capacitors are connected together electrically.What is the greatest possible capacitance of the combination?

Inserting a dielectric material between two charged parallel conducting plates,originally separated by air and disconnected from a battery,will produce what effect on the capacitor?

At what distance from a point charge of 7.3 μC would the electrical potential be 4.9 × 104 V? (ke = 8.99 × 109 N⋅m2/C2)

Two point charges of values +3.3 and +5.1 μC,respectively,are separated by 0.65 m.What is the potential energy of this 2-charge system? (ke = 8.99 × 109 N⋅m2/C2)

If C = 14 µF,what is the equivalent capacitance for the combination shown?

If a doubly-ionized oxygen atom (O-2)is accelerated from rest by going through a potential difference of 21 V,what will be the change in its kinetic energy?

A proton (+1.6 × 10−19 C)moves 15 cm on a path in the direction of a uniform electric field of strength 2.6 N/C.How much work is done on the proton by the electrical field?

An ion is released from rest and moves due to the force from an electric field from a position in the field having a potential of 14 V to a position having a potential of 8 V.The ion:

Introduction

Introduction: Part A

Motion in One Dimension

Motion in One Dimension: Part A

Vectors and Two-Dimensional Motion

Vectors and Two-Dimensional Motion: Part A

The Laws of Motion

The Laws of Motion: Part A

Energy

Energy: Part A

Momentum and Collisions

Momentum and Collisions: Part A

Rotational Motion and the Law of Gravity

Rotational Motion and the Law of Gravity: Part A

Rotational Equilibrium and Rotational Dynamics

Rotational Equilibrium and Rotational Dynamics: Part A

Solids and Fluids

Solids and Fluids: Part A

Thermal Physics

Thermal Physics: Part A

Energy in Thermal Processes Heat and Internal Energy

Energy in Thermal Processes Heat and Internal Energy: Part A

The Laws of Thermodynamics Work in Thermodynamic Processes

The Laws of Thermodynamics Work in Thermodynamic Processes: Part A

Vibrations and Waves

Vibrations and Waves: Part A

Sound

Sound: Part A

Electric Forces and Electric Fields

Electric Forces and Electric Fields: Part A

Electrical Energy and Capacitance: Part A

Current and Resistance Electric Current

Current and Resistance Electric Current: Part A

Direct-Current Circuits Sources of EMF

Direct-Current Circuits Sources of EMF: Part A

Magnetism Magnets

Magnetism Magnets: Part A

Induced Voltages and Inductance

Induced Voltages and Inductance: Part A

Alternating-Current Circuits and Electromagnetic Waves

Alternating-Current Circuits and Electromagnetic Waves: Part A

Reflection and Refraction of Light

Reflection and Refraction of Light: Part A

Mirrors and Lenses

Mirrors and Lenses: Part A

Wave Optics

Wave Optics: Part A

Optical Instruments

Optical Instruments: Part A

Relativity

Relativity: Part A

Quantum Physics Blackbody Radiation and Plancks Hypothesis

Quantum Physics Blackbody Radiation and Plancks Hypothesis: Part A

Atomic Physics

Atomic Physics: Part A

Nuclear Physics

Nuclear Physics: Part A

Nuclear Energy and Elementary Particles

Nuclear Energy and Elementary Particles: Part A

Particle Collisions, Mediating Photons, and Quark Structures: Exploring the Fundamentals of Physics

Filters

When charge Q₁ is placed at point P₁,the resulting potential at point P is V₁.When Q₂ is placed at point P₂ after Q₁ is in position at P₁,the resulting potential at P becomes V₂.What is the potential at point P if charge Q₁ is then removed?

A parallel-plate capacitor has a capacitance of 24 µF.What potential difference across the plates is required to store 6.8 × 10−⁴ C on this capacitor?

An electron is released from rest at the negative plate of a parallel-plate capacitor.If the distance across the plate is 6.0 mm and the potential difference across the plate is 4.0 V,with what velocity does the electron hit the positive plate? (m_e = 9.1 × 10−³¹ kg,e = 1.6 × 10−¹⁹ C)

At what distance from a point charge of 7.3 μC would the electrical potential be 4.9 × 10⁴ V? (k_e = 8.99 × 10⁹ N⋅m²/C²)

Two point charges of values +3.3 and +5.1 μC,respectively,are separated by 0.65 m.What is the potential energy of this 2-charge system? (k_e = 8.99 × 10⁹ N⋅m²/C²)

If a doubly-ionized oxygen atom (O^-2)is accelerated from rest by going through a potential difference of 21 V,what will be the change in its kinetic energy?

A proton (+1.6 × 10−¹⁹ C)moves 15 cm on a path in the direction of a uniform electric field of strength 2.6 N/C.How much work is done on the proton by the electrical field?