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Electrical and thermal conductivities of metals are due to the outer layer of electrons which are delocalized. The electrical conductivity as well as the electrons’ 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?

Electric Field Equation and Point Charges

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 your lab book the equati

Electric Potential/Separation of Variables

A rectangular pipe, running parallel to the z -axis (from −∞ to ∞), 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

Current Flow

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

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.

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

Electric Current

A highly sensitive ammeters can measure currents as small as 10.0 fA. How many electrons per second flow through a wire with a 10.0 fA current?

Calculating frequency and spring constant

1.) A 14kg motor is mounted on rubber feet. The motor can be pulled aside a distance of .5cmby a force of 200N. (a) Find the spring constant for the sideways motion of the motor. (b) What is the natural frequency for sideways vibration of the motor? (c) The motor is to rotate the drum of an electric dryer by means of a belt c

Electrostatics: Electric Force and Electric Field

Use Gauss's Theorem whenever possible: 1. Two point charges, one positive and the other, a negative charge, are separated by a small distance. (a) Determine the ratio q1/q2 ? (b) What are the signs of q1 and q2? (See attachment for all questions)

Electric Charge and Electric Field

How far apart must two protons be if the Coulomb force between them is equal to the weight of a single proton at the earth's surface? Assume that the two protons are far removed from any other charges. The charge of the proton is 1.60x10 -19 C, and its mass is 1.67x10 -27 kg.

Calculating angular speed and revolutions

An electric ceiling fan is rotating about a fixed axis with an initial angular velocity of 0.200 rev/s . The angular acceleration is 0.911 rev/s^2 . Its blades form a circle of diameter 0.720m . A) Compute the angular velocity of the fan after time 0.201 s has passed. Express your answer numerically in revolutions per second

Electric Potential vs. Electric Potential Energy

Hi. Can someone please explain to me what exactly the electric potential is and how it differs from electric potential energy -- not with equations, but in prose. (Or at least, with both.) I can read the equation, but I don't really understand what electric potential IS. What is its significance? Thank you!

Electric Fields and Electric Potential

Four quick conceptual questions: 1) Is the electric field (E = -delta V / delta s) always a positive number (or zero)? That is, is it always the absolute value of the magnitude of the electric field? Or can it have a negative value? 2) Is electric potential (delta V) always negative? The answer to one of the questions in m


Two positive chrages, when combined, give a total charge of +8.7 micro Couloumbs. When the charges are seperated by 3.00 meters, the force exerted by one charge on the other has a magnitude of 8.30E-3 Newtons. Find the amount of each charge.