Deck 24: Capacitors

Question 1

A parallel plate capacitor of capacitance C has plates of area A with separation d between them.When it is connected to a battery of voltage V,it has charge of magnitude Qon its plates.While it is connected to the battery,the distance between the plates is increased by a factor of 2 and the magnitude of the charge on the plates and the new capacitance are

A) Q,
C
B) Q,2C
C)2Q,2C
D)2Q,

Answer 1

Q,
C

Question 2

Consider a capacitor that consists of two parallel plates,one of which can move relative to the other.Air fills the space between the plates,the capacitance is 45.2 pF when the separation between plates is d = 0.360 cm.A battery with potential difference V=12.0 V is connected to the plates to fully charge them and then it is disconnected from the plates.The plates are moved to a new separation,d' and as a result the new potential difference V' between the plates is 10.0 V.What is the new plate separation,d'?

A)0.420 cm
B)0.240 cm
C)0.270 cm
D)0.180 cm
E)0.300 cm

Answer 2

0.300 cm

Question 3

Consider a capacitor that consists of two parallel plates,one of which can move relative to the other.Air fills the space between the plates,the capacitance is 25.0 pF when the separation between plates is d = 0.450 cm.A battery with potential difference V=11.1 V is connected to the plates.What is the charge density $\sigma$ on the left plate?

A)1.1 * 10^-8 C/m²
B)2.2 * 10^-8 C/m²
C)3.3 * 10^-8 C/m²
D)4.4 * 10^-8 C/m²
E)6.3 * 10^-8 C/m²

Answer 3

2.2 * 10^-8 C/m²

Question 4

A 3.0-nF parallel plate capacitor with a sheet of mylar (k = 3.1)filling the space between the plates is connected to a 150-V battery.While it is still connected to the battery,the sheet of mylar is completely removed from the space between the two plates.Determine the change in energy stored in the capacitor?

A)-1.0 * 10^-6 J
B)-2.4 * 10^-6 J
C)-4.9 * 10^-6 J
D)-5.5 * 10^-6 J

Question 5

A 2.0-nF parallel plate capacitor with a sheet of mylar (k = 3.1)filling the space between the plates is charged to a potential difference of 90 V and is then disconnected.How much work would be required to completely remove the sheet of mylar from the space between the two plates?

A)1.7 * 10^-5 J
B)3.5 * 10^-5 J
C)5.6 * 10^-5 J
D)8.1 * 10^-5 J

Question 6

A 1.00-nF capacitor initially charged to 30.0 V and a 2.00-nF capacitor charged to 40.0 V are connected to each other with the negative plate of each connected to the negative plate of the other.What is the electric potential across the 1.00-nF capacitor?

A)36.7 V
B)40.0 V
C)30.0 V
D)38.9 V
E)34.1 V

Question 7

A 1.50-µF capacitor charged to 40.0 V and a 2.40-µF capacitor charged to 15.0 V are connected to each other,with the positive plate of each connected to the negative plate of the other.What is the final charge on the 1.50-µF capacitor?

A)1.82 µC
B)5.74 µC
C)9.23 µC
D)15.8 µC
E)36.9 µC

Question 8

A 1.00-nF capacitor initially charged to 30.0 V and a 2.00-nF capacitor charged to 40.0 V are connected to each other with the negative plate of each connected to the negative plate of the other.What is the final charge on the 2.00-nF capacitor?

A)33.3 nC
B)73.3 nC
C)86.2 nC
D)100 nC
E)365 nC

Question 9

A 2.0-nF parallel plate capacitor with a sheet of mylar (k = 3.1)filling the space between the plates is charged to a potential difference of 90 V and is then disconnected.What is the potential difference between the plates of the capacitor once the mylar is completely removed?

A)1.0 * 10² V
B)2.8 * 10² V
C)3.4 * 10² V
D)5.1 * 10² V

Question 10

A 1.00-nF capacitor initially charged to 30.0 V and a 2.00-nF capacitor charged to 40.0 V are connected to each other with the negative plate of each connected to the negative plate of the other.What is the final charge on the 1.00-nF capacitor?

A)100 nC
B)86.2 nC
C)36.7 nC
D)365 nC
E)73.3 nC

Question 11

Capacitors connected in series always have the same

A)capacitance.
B)charge.
C)potential difference.
D)dielectric strength.

Question 12

Capacitors connected in parallel always have the same

A)capacitance.
B)charge.
C)potential difference.
D)dielectric strength.

Question 13

A 2.0-nF parallel plate capacitor with a sheet of mylar (k = 3.1)filling the space between the plates is connected to a 90 V battery.While it is still connected to the battery,the sheet of mylar is completely removed from the space between the two plates.Determine the change in the charge on one of the plates.

A)-1.0 * 10^-7 C
B)-1.2 * 10^-7 C
C)-1.4 * 10^-7 C
D)-1.6 * 10^-7 C

Question 14

Consider a capacitor that consists of two parallel plates,one of which can move relative to the other.Air fills the space between the plates,the capacitance is 45.2 pF when the separation between plates is d = 0.360 cm.A battery with potential difference V=12.0 V is connected to the plates to fully charge them and then it is disconnected from the plates.The plates are moved to a separation of 0.180 cm.What is the potential difference V' between the plates now?

A)6 V
B)10 V
C)18 V
D)24 V
E)36 V

Question 15

A 1.50-µF capacitor charged to 40.0 V and a 2.40-µF capacitor charged to 15.0 V are connected to each other,with the positive plate of each connected to the negative plate of the other.What is the final electric potential across the 1.50-µF capacitor?

A)12.5 V
B)6.15 V
C)40.0 V
D)25.0 V
E)8.13 V

Question 16

A parallel plate capacitor without dielectric and with capacitance C = 3.0 $\mu$ F is connected to a battery with potential difference V.A charge is stored on the capacitor.Now,a dielectric material ( )is inserted between the plates of this capacitor.After the dielectric has been inserted,what is the charge on the capacitor?

A)1.0 * 10^-5 C
B)2.7 * 10^-5 C
C)4.4 * 10^-5 C
D)6.3 * 10^-5 C
E)8.4 *10^-5 C

Question 17

When a capacitor has a charge of absolute value 80 µC on each plate the potential difference across the plates is 10 V.How much energy is stored in this capacitor when the potential difference across its plates is 120 V?

A)0.36 J
B)58 mJ
C)0.90 GJ
D)0.48 mJ
E)0.12 J

Question 18

A 1.50-µF capacitor charged to 40.0 V and a 2.40-µF capacitor charged to 15.0 V are connected to each other,with the positive plate of each connected to the negative plate of the other.What is the final charge on the 2.4-µF capacitor?

A)9.23 µC
B)36.9 µC
C)14.8 µC
D)1.82 µC
E)5.74 µC

Question 19

When N identical capacitors are connected in series across a battery,the energy stored is U.If the same capacitors were connected in parallel across the same battery,then how much energy would be stored?

A)U/N
B)U
C)NU
D)N²U

Question 20

When a capacitor has a charge of absolute value 40.0 µC on each plate the potential difference across the plates is 15.0 V.What is the potential difference across its plates when the energy is stored in this capacitor is 50.0 mJ?

A)137 V
B)0.516 mV
C)194 V
D)0.360 mV
E)0.155 V

Question 21

A 10-nF is connected in series with a 20-nF capacitor.This combination is then placed in parallel with a 30-nF capacitor.This combination is then placed parallel to a 9.0-V battery.What is the charge on the 20-nF capacitor.

A)60 nC
B)90 nC
C)140 nC
D)180 nC
E)330 nC

Question 22

A spherical shell capacitor is 1 cm in radius with the outside shell 1 mm beyond this.What is the capacitance of this combination?

A)21.3 pF
B)16.8 pF
C)12.2 pF
D)8.7 pF
E)5.7 pF

Question 23

A potential difference of V=24.0 V is applied across two capacitors in parallel,with capacitances 36.0 nF and 48.0 nF.What is the magnitude of the charge on one of the plates of the 36.0-nF capacitor?

A)1.2 * 10^-6 C
B)5.3 * 10^-7 C
C)3.4 * 10^-6 C
D)2.0 * 10^-6 C
E)8.6 * 10^-7 C

Question 24

Which of the following capacitors have the smallest charge?

A)a parallel plate capacitor with an area of 10 cm² and a plate separation of 2 mm connected to a 10-V battery
B)a parallel plate capacitor with an area of 5 cm² and a plate separation of 1 mm connected to a 10-V battery
C)a parallel plate capacitor with an area of 10 cm² and a plate separation of 4 mm connected to a 5-V battery
D)A parallel plate capacitor with an area of 20 cm² and a plate separation of 2 mm connected to a 20-V battery
E)All of the choices have the same charge.

Question 25

In circuit shown two identical parallel plate capacitors are connected.Initially the space between the plates of each capacitor is filled with air.If we wish to double the total amount of charge stored on both capacitors for the same applied voltage,which material should we use to fill the space between the plates?

A)Fill C₁ with glass (dielectric constant of 4)and leave C₂ alone.
B)Fill C₁ with Teflon (dielectric constant of 2)and leave C₂ alone.
C)Fill both C₁ and C₂ with Teflon (dielectric constant of 2).
D)Fill both C₁ and C₂ with glass (dielectric constant of 4).

Question 26

A potential difference of V=80.0V is applied across two capacitors in series,with capacitances 17.0 nF and 8.00 nF.What is the charge on the 17.0 nF capacitor?

A)1360 nC
B)1500 nC
C)435 nC
D)2000 nC
E)640 nC

Question 27

A proton traveling at speed of 1.0 * 10⁶ m/s enters the gap between the plates of a 2.0-cm-wide parallel-plate capacitor along x-axis.The surface charge densities on the plates are $\sigma$ = $\pm$ 1.0 * 10^-6 C/m².How far has the proton been deflected sideways ( $\Delta$ y)when it reaches the far edge of the capacitor? Assume the electric field is uniform inside the capacitor and zero outside.

A)1.33 mm
B)2.17 mm
C)4.7 mm
D)0.96 mm

Question 28

A 9-V battery is connected across a capacitor of 20 µF through a switch which is initially open.The amount of charge that flows from the battery to the capacitor when the switch is closed is

A)2.22 µC.
B)45 µC.
C)90 µC.
D)180 µC.
E)210 µC.

Question 29

What is the capacitance of a steel sphere of radius 5 mm?

A)0.4 pF
B)1 pF
C)0.8 pF
D)0.6 pF
E)1.5 pF

Question 30

Which of the following capacitors have the largest charge?

A)a parallel plate capacitor with an area of 10 cm² and a plate separation of 2 mm connected to a 10-V battery
B)a parallel plate capacitor with an area of 5 cm² and a plate separation of 1 mm connected to a 10-V battery
C)a parallel plate capacitor with an area of 10 cm² and a plate separation of 4 mm connected to a 5-V battery
D)A parallel plate capacitor with an area of 20 cm² and a plate separation of 2 mm connected to a 20-V battery
E)All of the choices have the same charge.

Question 31

A potential difference of V=80.0V is applied across two capacitors in series,with capacitances 17.0 nF and 8.00 nF.What is the magnitude of the electric potential across the 17.0 nF capacitor?

A)20.0 V
B)25.6 V
C)37.6 V
D)40.0 V
E)54.4 V

Question 32

An air-filled parallel plate capacitor is connected to a battery of voltage V_o.There is charge Q_o on each plate,energy U_o stored between the plates and an electric field of E_o between the plates.The capacitor remains connected to the battery and a dielectric material with a dielectric constant of K is then placed between the plates of the capacitor.What are the new values of V,Q,U,and E? V Q U E

A)V_o/K,KQ_o,U_o,E_o/K
B)KV_o,Q_o,K²U_o,E_o/K
C)V_o/K,Q_o,U_o/K,E_o/K
D)V_o,Q_o/K,U_o/K,E_o
E)V_o,KQ_o,KU_o,E_o

Question 33

An air-filled parallel plate capacitor is connected to a battery of voltage V_o.There is charge Q_o on each plate,energy U_o stored between the plates and an electric field of E_o between the plates.The capacitor is then removed from the battery and then a dielectric material with a dielectric constant of K is then placed between the plates of the capacitor.What are the new values of V,Q,U,and E?

A)V_o/K,KQ_o,U_o,E_o/K
B)KV_o,Q_o,K²U_o,E_o/K
C)V_o/K,Q_o,U_o/K,E_o/K
D)V_o,Q_o/K,U_o/K,E_o
E)V_o,KQ_o,KU_o,E_o

Question 34

What is the radius of a steel sphere having a capacitance of radius 1.5 pF?

A)9.0 mm
B)5.0 mm
C)170 mm
D)13 mm
E)6.0 mm

Question 35

A parallel plate capacitor has square plates of side L = 12 cm,and a distance d = 2 cm between the plates.Half of the capacitor area is filled with a dielectric of with k₁= 35.The other half is filled with a different dielectric with k₂ = 8.The effective (equivalent)capacitance of the capacitor is

A)6.4 * 10^-12
B)3.2 * 10^-12
C)2.7 * 10^-10
D)1.4 * 10^-10
E)1.1 * 10^-10

Question 36

A 10-nF is connected in series with a 20-nF capacitor.This combination is then placed in parallel with a 30-nF capacitor.This combination is then placed parallel to a 9.0-V battery.What is charge drawn from the battery?

A)60 nC
B)90 nC
C)140 nC
D)180 nC
E)330 nC

Question 37

A 6-V battery is connected across a capacitor through a switch which is initially open.The 90 µC charge flows from the battery to the capacitor when the switch is closed.The capacitance of the capacitor is

A)0.67 µF.
B)15 µF
C)20 µF
D)54 µF.
E)30 µF.

Question 38

The Earth has an electric field of 150 N/C near its surface.Find the electrical energy contained in a volume of air equal to the volume of a typical student (0.075 m³).

A)5.0 * 10^-11 J
B)7.5 * 10^-9 J
C)1.5 * 10^-8 J
D)1.0 * 10^-7 J
E)1700 J

Question 39

In circuit shown,calculate the charge on C₃,where $\varepsilon$ = 10 V,C₁ = C₂ = 6 $\mu$ F and C₃ = 3 $\mu$ F.

A)12 µC
B)36 µC
C)24 µC
D)9 µC

Question 40

A parallel plate capacitor connected to a 2-V battery consists of two 1-cm square plates separated by 1 mm of air.How much work is done in inserting a sheet with a dielectric constant of 1.5 between the plates (in units of 10^-13 J)?

A)17.4
B)9.67
C)8.85
D)4.53
E)2.28

Question 41

An uncharged parallel plate capacitor with an air gap is connected to a 6.0-V battery.After charging,the energy stored in the capacitor is 40 nJ.Without disconnecting the capacitor from the battery,a dielectric material is inserted into the air gap and an additional 200 nJ of energy flows from the battery to the capacitor.What is the dielectric constant of the material?

A)0.2
B)1.0
C)3.0
D)5.0
E)6.0

Question 42

Which of the following statements is TRUE?

A)A capacitor has its air gap doubled and its area halved.The capacitance is unchanged.
B)If the charge on one side of a capacitor is +Q,and the other side it is -Q,then the energy in the capacitor is Q²/C.
C)Two capacitors in series always have a lower capacitance than the capacitance of either of the two alone.
D)Two capacitors in parallel always have a lower capacitance than the capacitance of either of the two alone.
E)Two capacitors differ only in the dielectric material that fills them.For the same voltage,the one with the higher dielectric constant holds less charge.

Question 43

In the circuit shown,three capacitors with C1 = C2 = C3 = 10.00 $\mu$ F are connected to a battery with voltage V = 194 V.What is the voltage across capacitor C1 (in V)?

A)129.3
B)146.1
C)165.1
D)186.6
E)210.9

Question 44

Suppose we have two capacitors connected in series with a 10 V battery.What is the energy stored in the circuit if the capacitance of one is C₁ = 50 mF and the other is C₂ = 100 mF?

A)9.67 J
B)2.33 J
C)1.67 J
D)3.33 J
E)7.50 J

Question 45

A single parallel plate capacitor is constructed from two plates that have different areas.If this capacitor is initially uncharged and then connected to a battery,how will the amount of charge on the big plate compare to the amount of charge on the small plate?

A)The big plate will have more charge than the small plate.
B)The big plate will have the same charge as the small plate.
C)The big plate will have less charge than the small plate.
D)There is not enough information to determine an answer.

Question 46

Two metal plates,as shown in the figure,extend 5 cm into the page.The plates are machined in this shape to serve as electrodes in electrical equipment.The capacitance of this machined capacitor is

A)2.53 pF.
B)6.20 pF.
C)9.89 pF.
D)12.39 pF.
E)29.24 pF.

Question 47

If the Earth,radius 6371 km,was treated as a metallic sphere,and was given 15 kC of excess electric charge,what would the potential be on its surface?

A)21 MV
B)1.7 MV
C)11 V
D)130 V
E)3.3 V

Question 48

A dielectric with a dielectric constant of 3 is inserted into a parallel plate capacitor,filling one-half of the volume as shown in the figure.If the capacitance of the capacitor without the dielectric is C,what is the capacitance of the capacitor with the dielectric?

A)0.5 C
B)1 C
C)2 C
D)3 C
E)4 C

Question 49

A parallel plate capacitor is made of two circular thin plates of radius 15 cm separated by 2.5 mm of a material with dielectric constant 32.If they are charged to a potential difference of 22 V,what is the charge resident on each plate?

A)58 nC
B)180 nC
C)220 nC
D)700 nC
E)1.2 $\mu$ C

Question 50

A parallel plate capacitor is made of two circular thin plates of radius 15 cm separated by 2.5 mm of some unknown material.If they are charged to a potential difference of 22 V,what and the charge resident on each plate is 2.0 * 10^-7 C,what is the dielectric constant of the material in the space between the plates?

A)36
B)9.1
C)12
D)0.54

Question 51

Consider a parallel plate capacitor with area 1485 cm².The plates are separated by a distance 0.100 mm.The volume between the plates is filled with a material with a dielectric constant of 3.10.A voltage of 70.0 V is maintained across the plates using a battery.What is the charge stored in the capacitor (in $\mu$ C)?

A)2.14
B)2.85
C)3.79
D)5.04
E)6.71

Question 52

A battery is connected across a capacitor of 20 µF through a switch which is initially open.The 240 µC.of charge flows from the battery to the capacitor when the switch is closed.The electric potential provided by the battery is

A)9.0 V
B)12 V
C)6.0 V
D)24 V
E)48 V

Question 53

What is the total energy stored in the capacitors in the circuit shown?

A)1/2 CV²
B)3/2 CV²
C)2/3 CV²
D)1/3 CV²
E)5/2 CV²

Question 54

A parallel plate capacitor is made of two circular thin plates of radius 15 cm separated by 2.5 mm of air.If they are charged to a potential difference of 22 V,what is the charge resident on each plate?

A)1.8 nC
B)5.5 nC
C)7.0 nC
D)22 nC
E)36 nC

Question 55

High frequency signals are often transmitted along a coaxial cable,which consists of a wire surrounded by an outer grounded conductor.An insulating material fills the space between them and a plastic coating goes around the outside.For one such coaxial cable the radius of the inner wire is 0.5 mm and the radius of the outer conductor is 2.5 mm.The dielectric medium of constant $\kappa$ = 3.7 fills the space between the two conductors.The capacitance per unit length of this coaxial cable is

A)34.6 pF/m.
B)49.5 pF/m.
C)82.9 pF/m.
D)98.1 pF/m.
E)127.9 pF/m.

Question 56

If the Earth,radius 6371 km,was treated as a metallic sphere,and was charged to a potential of 110 V,what excess electric charge would reside on its surface?

A)5.0 * 10³ C
B)0.078 C
C)0.98 C
D)7.8 * 10^-5 C
E)9.8 * 10^-4 C

Question 57

Two parallel plate capacitors,C₁ and C₂ are connected in series to a 9.0-V battery.If capacitor C₁ has a capacitance of 10 nF and capacitor C₂ has a capacitance of 40 nF,what is the magnitude of the charge on each plate of capacitor C₂?

A)72 nC
B)90 nC
C)290 nC
D)360 nC
E)450 nC

Question 58

Ventricular fibrillation is a condition of heart dysfunction that can cause death.Under this condition,the heart quivers in an uncoordinated fashion as opposed to beating regularly.An electric shock to the chest can cause momentary paralysis of the heart muscle,after which the heart sometimes starts organized beating again.A defibrillator is a device that applies a strong electric shock to the chest over a few milliseconds.The device is a simple capacitor of several microfarads,charged to several thousand volts.Electrodes called paddles,about 8 cm across and coated with conducting paste,are held against the chest on both sides of the heart.Assume that one such defibrillator has capacitance of 25 µF and is charged to 4,200 Volts.If the capacitor completely discharges in 3.0 ms,the average power delivered to the chest by the defibrillator is

A)350.7 kW.
B)220.4 kW.
C)110.5 kW.
D)98.1 kW.
E)73.5 kW.

Question 59

An uncharged parallel plate capacitor with an air gap is connected to a 6.0-V battery.After charging,the energy stored in the capacitor is 40 nJ.If each of the plates has an area of 10 cm²,what is the magnitude of the electric field between the plates?

A)19 V/m
B)1.5 * 10⁶ V/m
C)3.0 * 10⁶ V/m
D)4.2 * 10⁶ V/m
E)6.0 * 10⁶ V/m

Question 60

Three capacitors of capacity 4,6,and 8 µF are connected in series with a battery of 13 V.The potential difference across the 6-µF capacitance is

A)4 V.
B)6 V.
C)8 V.
D)9 V.
E)10 V.

Question 61

A 0.2-mF capacitor is charged with 4 $\mu$ C positive on one plate and 4 $\mu$ C negative on the other.What is the voltage (V)on the capacitor?

A)200
B)400
C)0.020
D)0.040
E)110

Question 62

A capacitor consists of two circular parallel plates with diameter D.The plate separation is d,and there is a dielectric with constant k between the plates? Which of the following will double the capacitance.

A)double d
B)double D
C)halve d
D)halve D

Question 63

Two capacitors C₁ = 2.5 mF and C₂ = 5.0 mF are connected in parallel.If a voltage of V = 120 volts is applied across the capacitors,what is the energy stored in the capacitors?

A)4.0 J
B)36 J
C)54 J
D)12 J
E)0

Question 64

Two capacitors C₁ = 2.5 mF and C₂ = 5.0 mF are connected in series.If a voltage of V = 120 volts is applied across the capacitors,what is the energy stored in capacitor C₂?

A)4.0 J
B)36 J
C)54 J
D)12 J
E)0

Question 65

What is the capacitance of two parallel plates 0.9 mm apart with an area of 12 cm² if the space between the plates is filled with a material with dielectric constant of 3.7?

A)76 F
B)4.4 mF
C)130 $\mu$ F
D)3.7 $\mu$ F
E)44 pF

Question 66

Suppose we have two capacitors connected in parallel with a 10 V battery.What is the energy stored in the circuit if the capacitance of one is C₁ = 50 mF and the other is C₂ = 100 mF?

A)9.67 J
B)2.33 J
C)1.67 J
D)3.33 J
E)7.50 J

Question 67

In the circuit shown,what would be the equivalent single capacitor which would replace the three?

A)3 C
B)C/3
C)2 C/3
D)4 C/3
E)2 C

Question 68

Two capacitors C₁ = 2.5 mF and C₂ = 5.0 mF are connected in parallel.If a voltage of V = 120 volts is applied across the capacitors,what is the energy stored in capacitor C₂?

A)1.35 J
B)36 J
C)54 J
D)1.35 * 10⁶ J
E)0

Question 69

A point charge of 10 $\mu$ C is surrounded by water (dielectric constant = 80).What is the electric field 0.2 m away?

A)28 kN/C,radial outward
B)2.5 kN/C,radial inward
C)28 kN/C,tangential clockwise
D)2.5 kN/C,tangential counterclockwise
E)28 kN/C,radial inward

Question 70

If I want to build a parallel plate capacitor with capacitance 1 F,with a distance of 1 mm between the plates,and the gap filled with glass (dielectric constant 10.0),I would have to use square plates of side length

A)0.1 m.
B)0.3 m.
C)1.2 m.
D)3.1 m.
E)3.4 km.

Question 71

If I double the area of a capacitor and double the distance between its plates,the capacitance will be

A)doubled.
B)quadrupled.
C)unchanged.
D)halved.
E)one quarter.

Question 72

An air gap capacitor is charged up to 10 V and then disconnected.If a material is added to the gap between the plates and the voltage drops to 3.33 V,what is the dielectric constant of that material?

A)0.333
B)0.5
C)1.0
D)2
E)3

Question 73

Consider the assembly of capacitors shown here.Let C₁ = C₂ = C₃ = C₄ = 20 mF.What is the equivalent capacitance of this circuit?

A)10 mF
B)15 mF
C)30 mF
D)80 mF
E)40 mF

Question 74

Find the net force between two positively charged objects,each with charge of 1.2 mC,separated by a distance of 2.0m.They are in a material where the electric permittivity is 1.25 * 10^-11 C²/(N·m²).

A)2300 N
B)3200 N
C)6400 N
D)4600 N
E)2.6 * 10¹⁴ N

Question 75

What is the energy ( $\mu$ J)stored in the capacitors in this circuit?

A)72
B)36
C)162
D)60
E)0.333

Question 76

Two capacitors C₁ = 2.5 mF and C₂ = 5.0 mF are connected in series.If a voltage of V = 120 volts is applied across the capacitors,what is the energy stored in the capacitors?

A)4.0 J
B)36 J
C)54 J
D)12 J
E)0

Question 77

The equivalent capacitance for the three capacitors shown is

A)6 nF.
B)0.167 nF.
C)3.67 nF.
D)0.27 nF.
E)0.667 nF .

Question 78

Consider an isolated spherical conductor of radius R = 30 m,kept in a medium of permittivity 1.What is its capacitance?

A)0.29 nF
B)1.53 nF
C)3.34 nF
D)7.35 nF
E)53.5 nF