Exam 26: Potential and Field

A nonconducting sphere contains positive charge distributed uniformly throughout its volume.Which statements about the potential due to this sphere are true? All potentials are measured relative to infinity.(There may be more than one correct choice.)

The network shown in the figure is assembled with uncharged capacitors X,Y,and Z,with ,and and open switches,S₁ and S₂.A potential difference V_ab = +120 V is applied between points a and b.After the network is assembled,switch S₁ is closed for a long time,but switch S₂ is kept open.Then switch S₁ is opened and switch S₂ is closed.What is the final voltage across capacitor X?

A parallel-plate capacitor,with air between the plates,is connected across a voltage source.This source establishes a potential difference between the plates by placing charge of magnitude on each plate.The space between the plates is then filled with a dielectric material,with a dielectric constant of 7.74.What must the magnitude of the charge on each capacitor plate now be,to produce the same potential difference between the plates as before?

Two capacitors of capacitance 6.00 μF and 8.00 μF are connected in parallel.The combination is then connected in series with a 12.0-V voltage source and a 14.0-μF capacitor,as shown in the figure. (a)What is the equivalent capacitance of this combination? (b)What is the charge on the 6.00-μF capacitor? (c)What is the potential difference across the 6.00-μF capacitor?

Two thin-walled concentric conducting spheres of radii 5.0 cm and 10 cm have a potential difference of 100 V between them.(k = 1/4πε₀ = 8.99 × 10⁹ N ∙ m²/C²) (a)What is the capacitance of this combination? (b)What is the charge carried by each sphere?

Each plate of a parallel-plate air-filled capacitor has an area of 0.0020 ,and the separation of the plates is An electric field of is present between the plates.What is the surface charge density on the plates? (ε₀ = 8.85 × 10^-12 C²/N ∙ m²)

An ideal air-filled parallel-plate capacitor has round plates and carries a fixed amount of equal but opposite charge on its plates.All the geometric parameters of the capacitor (plate diameter and plate separation)are now DOUBLED.If the original energy stored in the capacitor was U₀,how much energy does it now store?

A 1.0-μF and a 2.0-μF capacitor are connected in series across a 3.0-V voltage source. (a)What is the charge on the 1.0-μF capacitor? (b)What is the voltage across the 2.0-μF capacitor?

Five capacitors are connected across a potential difference V_ab as shown in the figure.Because of the dielectrics used,each capacitor will break down if the potential across it exceeds 30.0 V.The largest that V_ab can be without damaging any of the capacitors is closest to

Three capacitors are connected as shown in the figure.What is the equivalent capacitance between points a and b?

The charge on the square plates of a parallel-plate capacitor is Q.The potential across the plates is maintained with constant voltage by a battery as they are pulled apart to twice their original separation,which is small compared to the dimensions of the plates.The amount of charge on the plates is now equal to

The capacitors in the network shown in the figure all have a capacitance of 5.0 µF.What is the equivalent capacitance,C_ab,of this capacitor network?

A parallel-plate capacitor has a capacitance of 10 mF and charged with a 20-V power supply.The power supply is then removed and a dielectric material of dielectric constant 4.0 is used to fill the space between the plates.How much energy is now stored by the capacitor?

The capacitive network shown in the figure is assembled with initially uncharged capacitors.A potential difference,V_ab = +100V,is applied across the network.The switch S in the network is kept open.Assume that all the capacitances shown are accurate to two significant figures.What is the total energy stored in the seven capacitors?

Two capacitors,C₁ and C₂,are connected in series across a source of potential difference.With the potential source still connected,a dielectric is now inserted between the plates of capacitor C₁.What happens to the charge on capacitor C₂?

An air-filled parallel-plate capacitor is connected to a battery and allowed to charge up.Now a slab of dielectric material is placed between the plates of the capacitor while the capacitor is still connected to the battery.After this is done,we find that

Three capacitors are arranged as shown in the figure.C₁ has a capacitance of 5.0 pF,C₂ has a capacitance of 10.0 pF,and C₃ has a capacitance of 15.0 pF.Find the voltage drop across the entire arrangement if the voltage drop across C₂ is 311 V.

An ideal parallel-plate capacitor consists of a set of two parallel plates of area A separated by a very small distance d.When this capacitor is connected to a battery that maintains a constant potential difference between the plates,the energy stored in the capacitor is U₀.If the separation between the plates is doubled,how much energy is stored in the capacitor?

Two square air-filled parallel plates that are initially uncharged are separated by 1.2 mm,and each of them has an area of 190 mm².How much charge must be transferred from one plate to the other if 1.1 nJ of energy are to be stored in the plates? (ε₀₀ = 8.85 × 10^-12 C²/N ∙ m²)

A parallel-plate capacitor consists of two parallel,square plates that have dimensions 1.0 cm by 1.0 cm.If the plates are separated by and the space between them is filled with teflon,what is the capacitance of this capacitor? (The dielectric constant for teflon is 2.1,and ε₀ = 8.85 × 10^-12 C²/N ∙ m².)