Exam 16: Electrical Energy and Capacitance

The dielectric strength of rutile is 6.0 × 10⁶ V/m,which corresponds to the maximum electric field that the dielectric can sustain before breakdown.What is the maximum charge that a 10−¹⁰-F capacitor with a 1.08-mm thickness of rutile can hold?

A "sandwich" is constructed of two flat pieces of metal (0.70 cm on a side)with a 1.0-mm-thick piece of a dielectric called rutile (κ = 100)in between them.What is the capacitance? (ε₀ = 8.85 × 10−¹² C²/N⋅m²)

A uniform electric field,with a magnitude of 650 N/C,is directed parallel to the positive x-axis.If the potential at x = 3.0 m is 1 700 V,what is the potential at x = 1.0 m?

An electron and a proton are each released from rest in the same uniform electric field.The electron moves a distance d_electron and the proton moves a distance d_proton as each particle's kinetic energy increases by 1.6 eV.How do d_electron and d_proton compare?

An electron is released from rest at the negative plate of a parallel-plate capacitor.If the distance across the plate is 2.0 mm and the potential difference across the plate is 6.0 V,with what velocity does the electron hit the positive plate? (m_e = 9.1 × 10−³¹ kg,e = 1.6 × 10−¹⁹ C)

Two particles each have the same mass but particle #1 has four times the charge of particle #2.Particle #1 is accelerated from rest through a potential difference of 10 V and attains speed v.Particle #2 is accelerated from rest also through a potential difference of 10 V.What speed does particle #2 attain?

Electrons in an x-ray machine are accelerated from rest through a potential difference of 60 000 V.What is the kinetic energy of each of these electrons in eV?

Three capacitors have capacitances C₁ < C₂ < C₃.If these capacitors are connected in series,which of the following is true for the resulting equivalent capacitance?

If two parallel,conducting plates have equal positive charge,the electric field lines will:

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:

Equipotential surfaces around a point charge are

At what distance from a point charge of 8.0 μC would the electrical potential be 4.8 × 10⁴ V? (k_e = 8.99 × 10⁹ N⋅m²/C²)

A proton (+1.6 × 10−¹⁹ C)moves 20 cm on a path in the direction of a uniform electric field of strength 2.4 N/C.How much work is done on the proton by the electrical field?

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

How much charge can be placed on a capacitor of plate area 15 cm² with air between the plates before it reaches "atmospheric breakdown" where E = 3.0 × 10⁶ V/m? (ε₀ = 8.85 × 10−¹² C²/N⋅m²)

A parallel-plate capacitor with plate area A and plate separation d has a capacitance of 4 μF with the gap between the plates unfilled.The gap is then filled with two dielectric materials,one with dielectric constant 2 and the other one with dielectric constant 6.Each slab of dielectric has area A and thickness d/2,the layering of the dielectrics 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?

What is the equivalent capacitance between points a and b? All capacitors are 5.0 μF.

A pair of parallel plates,forming a capacitor,are charged.The plates are pulled apart to quintuple the original separation,the charges on the plates remaining the same.What is the ratio of the final energy stored to the original energy stored?

Increasing the separation of the two charged parallel plates of a capacitor,which are disconnected from a battery,will produce what effect on the capacitor?

Two capacitors with capacitances of 1.5 μF and 0.25 μF,respectively,are connected in parallel.The system is connected to a 40-V battery.What electrical potential energy is stored in the 1.5-μF capacitor?