Exam 20: Electric Potential and Electric

Each plate of a parallel-plate air-filled capacitor has an area of 0.0040 ,and the separation of the plates is An electric field of Is present between the plates.What is the energy density in the region between the plates? (ε₀ = 8.85 × 10^-12 C²/N ∙ m²)

An alpha particle (a helium nucleus,having charge +2e and mass 6.64 × 10^-27 kg)moves head-on at a fixed gold nucleus (having charge +79e).If the distance of closest approach is 2.0 × 10^-10 m,what was the speed of the alpha particle when it was very far away from the gold? (k = 1/4πε₀ ,

Four point charges of magnitude 6.00 μC and are at the corners of a square 2.00 m on each side.Two of the charges are positive,and two are negative.What is the electric potential at the center of this square,relative to infinity,due to these charges? (k = 1/4πε₀ = 8.99 × 10⁹ N ∙ m²/C²)

Which statements must be true about the surface of a charged conductor in which no charge is moving? (There could be more than one correct choice. )

An ideal air-filled parallel-plate capacitor with horizontal plates has a plate separation of 5.0 cm.If the potential difference between the plates is 2000 V,with the top plate at the higher potential,what are the magnitude and direction of the electric field between the plates?

An ideal parallel-plate capacitor has a capacitance of C.If the area of the plates is doubled and the distance between the plates is halved,what is the new capacitance?

A small 4.0-µC charge and a small 1.5-µC charge are initially very far apart.How much work does it take to bring them to a final configuration in which the 4.0-µC charge is at the point x = 1.0 mm,y = 1.0 mm,and the 1.5-µC charge is at the point x = 1.0 mm,y = 3.0 mm? (k = 1/4πε₀ = 8.99 × 10⁹ N ∙ m²/C²)

If the electric potential at a point in space is zero,then the electric field at that point must be

A +4.0-μC and a -4.0-μC point charge are placed as shown in the figure.What is the potential difference between points A and B? (k = 1/4πε₀ = 9.0 × 10⁹ N ∙ m²/C²)

A point charge of +3.00 μC and a second charge Q are initially very far apart.If it takes Of work to bring them to a final configuration in which the Charge is at the point x = 1.00 mm,y = 1.00 mm,and the second charge Q is at the point x = 1.00 mm,y = 3.00 mm,find the magnitude of the charge Q.

A proton that is initially at rest is accelerated through an electric potential difference of magnitude 500 V.What speed does the proton gain? (e = 1.60 × 10^-19 C,m_proton = 1.67 × 10^-27 kg)

An ideal air-filled parallel-plate capacitor consists of two circular plates,each of radius How far apart should the plates be for the capacitance to be 300.0-pF? (ε₀ = 8.85 × 10^-12 C²/N ∙ m²)

A +5.0-µC point charge is 12 cm from a -5.0-µC point charge.What is the magnitude of the electric field they produce at the point on the line connecting them where their electric potential (relative to infinity)is zero? (k = 1/4πε₀ = 9.0 × 10⁹ N ∙ m²/C²)

How much energy is necessary to place three +2.0-µC point charges at the vertices of an equilateral triangle of side 2.0 cm if they started out extremely far away? (k = 1/4πε₀ = 9.0 × 10⁹ N ∙ m²/C²)

An ideal parallel-plate capacitor consists of two parallel plates of area A separated by a distance d.This capacitor is connected to a battery and charged until its plates carry charges +Q and -Q,and the battery is then disconnected.If the separation between the plates is now doubled,the electrical energy stored in the capacitor will

A parallel-plate capacitor is connected to a battery and becomes fully charged.The capacitor is then disconnected,and the separation between the plates is increased in such a way that no charge leaks off.As the plates are being separated,the energy stored in this capacitor

A 5.0 μF capacitor has a potential difference of 5.0 V. Applied across its plates.If the potential difference across its plates is increased to 8.0 V. How much additional energy does the capacitor store?

When the magnitude of the charge on each plate of an air-filled capacitor is 4 μC,the potential difference between the plates is 80 V.What is the capacitance of this capacitor?

Two 3.0 μC charges lie on the x-axis,one at the origin and the other at What is the potential (relative to infinity)due to these charges at a point at On the x-axis?

In a region where the electric field is uniform and points in the +x direction,the electric potential is -2000 V at x = 8 m and is +400 V at x = 2 m.What is the magnitude of the electric field?