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# Electric

Electrical and thermal conductivities of metals are due to the outer layer of electrons which are delocalized. The electrical conductivity as well as the electronsâ€™ conductivity, to the heat capacity and head conductivity of metals can be calculated from the free electron model. This does not take into account the detailed structure of the ion lattice.

When considering the electronic band structure and binding energy of a metal, it is important to take into account the positive potential caused by the specific arrangement of the ion cores, which is periodic in crystals. The important consequence of the periodic potential is the formation of a small band gap at the boundary of the Brillouin zone. The potential of the ion cores can be treated by various mathematical models. The simplest model is the nearly free electron model.

Metals have strong conducting abilities which are often utilized in electrical appliances and for carrying an electric current over a distance with little energy lost. Electrical power grids rely on metal cables to distribute electricity as well as home electrical systems. For example, home electrical systems are mostly wired with copper wire for its strong conducting properties.

### Physics: Find the Electric Field on Any Point on a Y-Axis

5.) A square of paper measuring a on a side carries a total charge +q which is uniformly distributed over its surface. The square lies in the x-y plane with its center at the origin and its sides parallel to the coordinate axes. Find the electric field on any point on the y-axis with y > a. Show that this square looks like a poi

### Electric Charge: Electrons and Net Attraction

See the attached file. 1.) When you pull two socks out of a clothes dryer they stick to each other due to an accumulation of static charge. How many electrons are responsible for this net attraction? Let?s make an estimate following these steps: A sock has a mass of about 15g. How large (in newtons) is the gravitational f

### The Electric Potential Outside a Sphere With Given Potential

A conducting spherical shell of radius R is cut in half. The two hemispherical pieces are electrically separated from each other but are left close together, so that the distance separating the two halves may be neglected. The upper half is maintained at Phi=Phi0 and the lower half is maintained at phi=0. Find the electrostatic

### Quantum physics: Properties of particles

Please see the graphic in the problem attached. This question is about how the properties of particles may be found from their constituent parts, and how these relate to the forces between them. 1(a) What are the electric charges of the baryon and antibaryon formed from the following combination of quarks and antiquarks?

### Solving Poisson equation in 2D IN MATLAB

2D Electrostatic with boundary condition 0<=x<=1,0<=y<=1 A charged wire is located at xo and yo and parallel to the axis of a uniform, square, hollow, conducting channel. After factoring out the constants, poisson equation for electric potential is Del square u(x,y)=-delta(x-x0)*delta(y-y0) The boundary condition at the

### Potential phi as a function of x, y and z in the vicinity of the ring axis

A thin circular ring of radius R lies in x-y plane and consists of two homogeneously opposite charged halves with charges q at x>0 and -q at x<0. Find the potential phi as a function of x, y and z in the vicinity of the ring axis (x,y<<(R^2+z^2)/R) to linear order in x and y. Answer is: phi= q*R*x/(pi^2*epsilonnot*(R^2+z^2

### Ranking Charges

Consider the three charges shown below. They are all equal in magnitude (but the signs are indicated) and are equally separated along the x-axis. Rank these charges in order of the magnitude of the electric force they experience, starting with the largest force (rank 1) and going to the smallest (rank 3). charge A charge C ch

### Dirac delta function problem

(a) Write an expression for the electric charge density p (r) of a point charge q at r/. Make sure that the volume integral of p equals q. (b) What is the charge density of an electric dipole, consisting of a point charge -q at the origin and a point charge +q at a? (c) What is the charge density of a uniform, infini

### Determining the Potential of Two Charges: Example Problem

Part 1: A charge of -4.176 Î¼C is located at (5.079 m, 6.546 m), and a charge of 1.879 Î¼C is located at (-1.502 m, 0). Calculate the electric potential at the origin. Part 2: There is one point on the line connecting these two charges where the potential is zero. What is the x-coordinate of this point?

### Placing a Third Charge between Two Charges: Example Problem

A charge of 1.56E-9 C is placed at the origin, and a charge of 3.75E-9 C is placed at x = 1.27 m. Locate the point between the two charges at which a charge of 2.97E-9 C should be placed so that the net electric force on it is zero. Please explain each step.

### Electrostatics: Potential Due to Varying Charge Density

a. dielectric sphere of radius R is polarized so that P=(k/r)r1, r1 being the unit radial vector. c. Calculate the potential inside/outside the sphere d. Sketch a curve of potential versus distance from r=0 to r=infinity.

### Electric Field Equation and Point Charges

See the attached file. Activity Three: Place a positive charge and a negative charge close to each other to create a dipole. Again, predict what the field will look like. Then, test your prediction. If your observation is different than your prediction, explain here what was wrong in your original thinking. Include in yo

### Electric potential due to electric dipole

Write down an expression for the electric potential about an electric dipole, as a function of the spatial coordinates relative to the dipole. Calculate the electric field as a function of these spatial coordinates from the electric potential. A 2D solution (with the dipole existing in the 2D plane) is fine. Thanks

### Electric Potential/Separation of Variables

A rectangular pipe, running parallel to the z -axis (from &#8722;&#8734; to &#8734;), has three grounded metal sides, at y = 0, y = a, and x = 0. The fourth side, at x = b, is maintained at a potential V0 (a constant). (a) What is the potential within the pipe? (b) Use a plotting program like Maple to plot the solution

### the current flowing through the body

A person accidentally touches an electrical socket with both hands. By modeling the arm and the chest to be a cylindrical tube with a total length L = 2.0m, cross-sectional area A = 10^2, and resistivity rho = 1.5 ohmm, you can calculate the current in amperes through the person when a potential difference of V = 110V is applied

### Electric Dipole in an Electric Field

Point charges q1=- 5.00 nC and q2=+ 5.00 nC are separated by distance 3.80 mm, forming an electric dipole. A) Find the magnitude of the electric dipole moment in Cm. B) The charges are in a uniform electric field whose direction makes an angle 36.5 degrees with the line connecting the charges. What is the magnitude of this

### Coulomb's Law: Finding Magnitude and Direction

An electric dipole consists of 2 point objects with equal and opposite charges as shown. The charged objects are 20cm above & below the horizontal axis. Point P is 40cm away from both charges. Find magnitude and direction of the electric force on an object with a charge of 2 uC at point P.

### Electric field and electric force of the point charge

See attached file for full problem description. 1. What is the force on the 5 nC charge 2. What is the force on the 1 nC charge at the bottom? Fx, / Fy=? 3. Charge q2 is in static equilibrium. What is q1 in nC?

### Electric Force Between Two Charged Spheres

When the distance between the centers of two charged spheres is increased by 10%, how much does the magnitude of the electric force on one of the spheres change? A. If the two spheres both have the same sign charge, the force decrease about 20\$ , but if they have opposite charge it increases by about 20% B. The force must de

### Electric Field Charge

Please see attached file 4. for the following problems: 6. At each point on the surface of the cube shown in Figure 23-27, the electric field is parallel to z-axis. The length of each edge of the cube is 3.0 m. On the top face of the cube, E = -34k N/C, and at the bottom face E = +20k N/C. Determine the net charge contained w

### Equi-potential Surfaces

An equi-potential surface that surrounds a =3.0 x 10^-7 -C point charge has a radius of 0.15 m. What is the potential of this surface?

### Electric field discrete charge distribution

1) How many coulombs of positive charge are there in kg of carbon? Twelve grams of carbon contain Avogadro's number of atoms, with each atom having six protons and six electrons. 2) Three charges, each of magnitude nC, are at separate corners of a square edge of length 5 cm. The two charges at opposite corners are positive,

### Charges on a metal sphere

1. a metal sphere has a charge of +8.0 micro C. What is the charge after 6.0 x 10^13 electrons have been placed on it? 2. Two Charge attract each other with force of 1.5N. What will be the force if the distance is reduced to one ninth of it original value.

### Brewster's Angle phenomenonn using Electric field of an oscillating electric dipole

Explain Brewster's Angle phenomenon with the help of "Electric field of an oscillating electric dipole."

### Electric Potential and Electric field

(See attached file for full problem description with diagram) (1) Two point charges, Q1 = +2 x 10-6 C and Q2 = -3 x 10-6 C, are situated as shown. (Refer to the attached file to view the diagram) (a) Find the electric potential at point A and at point B. (b) Find the work needed to move a point charge Q3 = 5 x 10-6 C f

### 3 Q Electric Field: Point Charges, Ring, Sphere, Gauss,

I am really having trouble understanding the concepts of these problems because I have found the median of each side of the triangle to find the center then using geometry i was able to figure out the angles but i am completely lost on what to do next! Please can some one explain to me how to do this problem! 1)Three electri

### Potential Inside a Box

A rectangular box with x dimension a, y dimension b, and z dimension c is depicted in the diagram. If the electric potential on all sides except z=c is zero, and the potential on the side z=c is V(x,y), Find the potential inside the box.

### Electric Potential and Electric Potential Energy

A point charge of -6.8 ÂµC is at the origin. (a) What is the electric potential due to this charge at (-2.0 m, 0)? (b) What is the electric potential to this charge at (2.0 m, -2 m)?

### Electric Field Electric potential and Coulomb Force

1. The diagram shows the electric field due to a point charge. Determine if the point charge is positive or negative. Find the location of the charge. Draw it on the diagram. (See diagram) 2. Can you assign charges for the following four cases, so that these forces are correct? (See diagram) 3. Figure below shows three poi

### Physics: Magnitude of the electric field in a cell membrane. And electric potential at unknown location B between two points.

Please review the attached two problems, write how to solve every step so I can learn how to do these. Please only use algebra based formulas. --- The inner and outer surfaces of a cell membrane carry a negative and positive charge, respectively. Because of these charges, a potential difference of about 0.065 V exists across