Exam 25: Electric Potential

A particle (charge 7.5 μC)is released from rest at a point on the x axis,x = 10 cm.It begins to move due to the presence of a 2.0-μC charge which remains fixed at the origin.What is the kinetic energy of the particle at the instant it passes the point x = 1.0 m?

A charge of 4.0 nC is distributed uniformly along the x axis from x = +4 m to x = +6 m.Which of the following integrals is correct for the electric potential (relative to zero at infinity)at the origin?

A charge of 20 nC is distributed uniformly along the y axis from y = 0 to y = 4 m.Which of the following integrals is correct for the electric potential (relative to zero at infinity)at the point x = +3 m on the x axis?

A series of 3 uncharged concentric spherical conducting shells surround a small central charge q.The potential at a point outside the third shell,at distance r from the center,and relative to V = 0 at ∞,is

In the Bohr model of the hydrogen atom,the electron circles the proton at a distance of 0.529 × 10−¹⁰ m.Find the potential at the position of the electron.

The electric potential at the surface of a charged conductor

An electron is released form rest in a region of space where a uniform electric field is present.Joanna claims that its kinetic and potential energies both increase as it moves from its initial position to its final position.Sonya claims that they both decrease.Which one,if either,is correct?

Particle A (mass = m,charge = Q)and B (mass = m,charge = 5 Q)are released from rest with the distance between them equal to 1.0 m.If Q = 12 μC,what is the kinetic energy of particle B at the instant when the particles are 3.0 m apart?

Points A [at (2,3)m] and B [at (5,7)m] are in a region where the electric field is uniform and given by N/C)What is the potential difference V_A − V_B?

Equipotentials are lines along which

Three identical point charges (+2.0 nC)are placed at the corners of an equilateral triangle with sides of 2.0-m length.If the electric potential is taken to be zero at infinity,what is the potential at the midpoint of any one of the sides of the triangle?

A 60-μC charge is held fixed at the origin and a −20-μC charge is held fixed on the x axis at a point x = 1.0 m.If a 10-μC charge is released from rest at a point x = 40 cm,what is its kinetic energy the instant it passes the point x = 70 cm?

When a charged particle is moved along an electric field line,

Identical point charges (+20 μC)are placed at the corners of an equilateral triangle with sides of 2.0-m length.How much external energy is required to bring a charge of 45 μC from infinity to the midpoint of one side of the triangle?

Three charged particles are positioned in the xy plane: a 50-nC charge at y = 6 m on the y axis,a −80-nC charge at x = −4 m on the x axis,and a 70-nc charge at y = −6 m on the y axis.What is the electric potential (relative to a zero at infinity)at the point x = 8 m on the x axis?

Two particles,each having a mass of 3.0 μg and having equal but opposite charges of magnitude of 6.0 nC,are released simultaneously from rest when they are a very large distance apart.What distance separates the two at the instant when each has a speed of 5.0 m/s?

The electric field in the region defined by the y-z plane and the positive x axis is given by E = ax,where a is a constant.(There is no field for negative values of x. )As x increases in magnitude,relative to V = 0 at the origin,the electric potential in the region defined above is

The electric field in a region of space is given by E_x = (3.0x)N/C,E_y = E_z = 0,where x is in m.Points A and B are on the x axis at x_A = 3.0 m and x_B = 5.0 m.Determine the potential difference V_B − V_A.

Identical 2.0-μC charges are located on the vertices of a square with sides that are 2.0 m in length.Determine the electric potential (relative to zero at infinity)at the center of the square.

A charge of +3.0 μC is distributed uniformly along the circumference of a circle with a radius of 20 cm.How much external energy is required to bring a charge of 25μC from infinity to the center of the circle?